THE first strike came without warning, just before noon, as children were walking home from school for lunch and their mothers were waiting on the doorsteps.
Inside the police headquarters of Gaza City, new recruits in black uniforms with red berets were standing in ranks in the sunny courtyard of the security compound, receiving medals at a graduation ceremony.
Minutes later, 15 of them were lying dead on the ground as pools of blood streamed into the dust.
Nearby, their surviving colleagues shrieked in terror as more waves of Israeli rockets hit their targets. It was the beginning of an onslaught.
Yesterday's bombing of Gaza City and the towns along the Israeli border was unprecedented in its severity, as Israel's warplanes and helicopters dropped an estimated 100 tonnes of bombs on the densely populated area in a few hours.
The Israeli attack obliterated more than 30 of Gaza's security compounds across the city and surrounding towns, killing at least 225 and injuring about 700.
Israeli officials insisted the attacks, which continued throughout the afternoon, targeted "terrorist infrastructure" following days of rocket attacks from Gaza on southern Israel that caused some damage but few injuries.
But the compounds, headquarters for the Hamas police force, were almost all buried deep in residential areas, many with schools close by. Some of the Israeli missiles struck as children were leaving school, and women rushed into the streets looking frantically for their children.
At the main police headquarters, which was hit at noon by Israeli rockets, rescue workers beat their heads and shouted "God is greatest."
A badly wounded man lying nearby quietly recited verses from the Koran. Hamas called the assault a "massacre". Another survivor could only raise his index finger in a show of Muslim faith, uttering a prayer.
Hamas estimated at least 140 members of its security forces had been killed, including Gaza police chief Tawfiq Jabber and the head of Hamas's security and protection unit.
But in one of the bloodiest days of the Israeli-Palestinian conflict, the death toll was almost doubled by civilian casualties as bodies piled up outside the hospitals and children disappeared in the chaos and rubble of the attacks.
Shopkeeper Said Masri sat in the middle of a destroyed Gaza City street, close to a security compound, alternately slapping his face and covering his head with dust from the bombed-out building.
"My son is gone, my son is gone," wailed Masri, 57. He said he sent his nine-year-old son out to buy cigarettes minutes before the air strikes began and now could not find him.
Ayman Mohyeldin, Al Jazeera's correspondent in Gaza, was in the middle of several attacks. He said: "A series of explosions were heard over Gaza City. From where we were, there were at least seven different clouds of smoke from the strikes. We were seeing some casualties being evacuated in cars."
A missile hit the town of Netivot, about a mile west of Gaza City, killing an Israeli man and wounding four people. Dozens of stunned residents gathered around the house that took the deadly rocket hit. Many wept openly. The crowd broke up after an alert siren went off and sent the onlookers running.
On a construction site in Jabaliya, north of Gaza City, Tamer Kahrouf, 24, said he saw his two brothers and uncle killed when the Israeli planes bombed a security post nearby. Kharouf, wounded and bleeding from the head, had been working on the site when the bomb hit.
Closer to the Israeli border, in the town of Sderot, which was pummelled hardest by the rockets, the streets were nearly empty.
A few cars carried panicked residents out of the city, and dozens congregated on a hilltop to watch the Israeli aerial attacks as columns of thick black smoke rose from the nearby towns and sirens rang out.
At a hospital in Rafah, a large town on the border of Israel and Gaza, friends and relatives dragged their loved ones into wards and demanded treatment for them.
Men, women and children, blood pouring from their wounds, lined up outside the hospital, waiting for the attention of a doctor.
Hospitals in Gaza City also struggled to cope with the large numbers of injured, piling three children on a single bed while a constant stream of wounded arrived in cars and vans.
Inside Shifa Hospital, Gaza's main treatment centre, relatives carried a five-month-old baby who had suffered a serious shrapnel wound to the head. Overwhelmed hospital staff seemed unable to offer help.
One doctor said: "We are treating people on the floor, in the corridors. We have no more space. We don't know who is here or who to treat first."
Outside the front of the hospital, scores of dead bodies were laid out waiting for family members to identify them. For many it would be a horrible, even impossible, task: many corpses were dismembered and some were headless.
Health officials appealed for outside help. "We lack everything, medical equipment, anaesthesia, bandages, fuel for ambulance vehicles, medicine, everything," cried Muawiyah Hassanein, head of Gaza's ambulance and emergency department.
"What happened was unexpected and our hospitals were neither ready nor prepared to receive such huge numbers of casualties."
But Israeli warplanes kept up attacks on targets in Gaza after darkness fell, striking at a metal foundry and other sites in the south of the coastal strip.
Women braved the streets as evening fell, wailing as they searched for their relatives among the dead. Sawsan Al-Ajab, 50, made her way to the main police station in Gaza City looking for two sons, aged 32 and 24, who both worked there.
Umm Mohammed went back to the office she had been working in. "It is a war. Look at the smoke, look at the bodies and the body parts, it is like Afghanistan or Iraq," she said as she looked over one flattened Hamas office.
In the wake of the worst offensive Israel has ever delivered on Gaza, Hamas quickly vowed revenge, ordering "all fighters to respond to the Israeli slaughter".
It did not say what form this action would take but one fighter, maddened by the sight of the mangled bodies of his comrades, said suicide bombers would blow themselves up in Israeli restaurants, cafs and streets.
Yesterday, Hamas said all its security installations were hit, and fired at least 50 medium-range Grad missiles at Israel in response, reaching deeper into its territory than in the past.
One Israeli was killed and at least six people were wounded in the rocket attacks yesterday, a count that is likely to increase over the next week.
Hamas leaders released a statement about future retaliation, saying: "All options are open to the Palestinian resistance to strike the Zionist enemy. One leader will be replaced by a hundred leaders."
Defiant Hamas leaders said they "will continue the resistance until the last drop of blood", while Israel told its civilians near Gaza to take cover as militants began retaliating with rockets.
'The doctor told me the child had no chance of survival'
Pauline McNeill MSP is a lifelong campaigner for the Palestinian cause and recently visited Gaza to meet local parliamentarians. Here she describes what she saw.
WHEN I visited Gaza with a group of politicians earlier this year, I hoped I would never witness anything more shocking than the degradation and deprivation that have been visited on that tiny parcel of land.
There I visited a hospital and saw a 12-week-old baby suffering from hypothermia lying helplessly in the neonatal unit. With great sadness the doctor told me that the child had no chance of survival because the incubator was worn out.
The loss of that tiny life is just one tragic aspect of life in one of the world's most war-torn troublespots, which has now once again found itself deep in conflict.
When 11 European parliamentarians, including myself and Hugh O'Donnell and Sandra White from Holyrood, took the 15-hour trip on the boat Dignity from Cyprus to Gaza, our eyes were well and truly opened.
As we were taken around the hospitals, we were shocked to see so many youngsters suffering from diseases such as rickets – vitamin deficiency conditions that have long been banished from the more affluent parts of the world.
We were told that 200 cancer sufferers had died unnecessarily because the Israeli authorities prevented them from travelling to the more up-to-date hospitals in Egypt and Israel.
Gastroenteritis was rife, while 50% of children were suffering from some form of malnutrition.
There was a lack of sterile equipment and a desperate shortage of the most basic treatments such as antibiotics and painkillers. Quite how this woefully under-resourced health system is dealing with the carnage that has today been visited on Gaza I cannot imagine.
Motorists and industry were hampered by a drastic fuel shortage. The Israeli-controlled power plant was not running at full capacity.
One person we met was Andrew Muncie, a Scot who was recently reported as having been abducted by the Israeli navy.
He is one of the many foreign nationals whom we met on our visit who go out fishing with fishermen in an attempt to prevent the Israeli navy from shooting at their boats. The support that those foreign nationals have given fishermen has been a success: catch levels are up 20-fold.
Restrictions limiting boats to fishing within five miles of the shore contributed to a food shortage and resulted in catches that were contaminated by a hopelessly inadequate sewage system.
A trip to one of the larger towns in Gaza with 200,000 inhabitants revealed just how poor the infrastructure is. The sewage plant had burst. Sewage was strewn all over the streets, but the town only had one truck that was capable of pumping out the sewage.
Heavy rainfall and water damage had created massive holes in the pavements, but nothing could be repaired. There was no cement and there were no spare parts.
The misery caused by a damaged sewage system, however, could not compare with the tragic stories we heard from mothers still looking for their missing sons.
We sat down with a group of mums, none of whom had seen their sons for seven or eight years. They assumed they had been charged and arrested by the Israelis, but they did not really know why.
They thought some of them were held in underground prisons. Of course, it may be that they had committed an offence and deserved to be charged, but there are rules under international law about the conditions in which prisoners have to be held. We also heard stories of thousands of political prisoners, who were being held but had no contact with their families.
Schoolchildren cannot aspire to achieve their chosen careers because unemployment is now above 50%. University life is impossible. Teachers cannot travel to learn. The mental health problems of people who live under permanent siege are acute, yet there are no mental health services in Gaza.
According to Medical Aid for Palestinians, 71% of children say when interviewed that they want to be a martyr. That is shocking to many people. Of course, if the situation is not tackled, generations of young Palestinians will be lost to conflict. The blockage can lead only to further tension and conflict.
Ten days ago, I put my name to a debate in the Scottish Parliament which called for dignity for Palestinians. During that debate, I recalled that Desmond Tutu described the situation in Gaza as an "abomination", and Mary Robinson said that it is almost unbelievable that the world does not seem to care about a whole civilisation being destroyed. We in Scotland must play a part in exposing that human tragedy.
This attack simply emphasises in the most tragic way imaginable that we must continue that work.
This has been brought home to me with the messages I received today.
The friends that I have made during various trips have been emailing me, describing the horrific scenes they are having to deal with, including one journalist contact who told me that the mother of one of his friends had been killed in the attacks.
It is extremely shocking and depressing that there has been such an appalling death toll in a part of the world which has been under siege for so long. The world needs to wake up and do something about it.
Hamas: the gunmen who ended up in government
THE name Hamas, an abbreviation of Harakat al-Muqawama al-Islamiyya or Islamic Resistance Movement, first appeared in 1987.
It was emblazoned on leaflets accusing the Israeli intelligence services of undermining the moral fibre of Palestinian youth.
Since then the organisation has risen from being a small militant group to a formidable and powerful organisation which remains hugely popular among dispossessed Palestinians despite being classified as a terror group by the European Union and United States.
The movement's controversial status remained, and increased, in January 2006 when it entered politics and scored a dramatic win in the Palestinian parliamentary elections.
The feared and revered group is the largest Palestinian militant Islamist organisation, formed in 1987 at the beginning of the first intifada, or Palestinian uprising against Israel's occupation in the West Bank and Gaza.
The group's short-term aim has been to drive Israeli forces from the occupied territories. To achieve this it has launched attacks on Israeli troops and settlers in the Palestinian territories and against civilians in Israel.
It also has a long-term aim of establishing an Islamic state on all of historic Palestine – most of which has been contained within Israel's borders since its creation in 1948.
Hamas came to prominence after the first intifada as the main Palestinian opponent of the Oslo accords – the US-sponsored peace process that oversaw the gradual and partial removal of Israel's occupation in return for Palestinian guarantees to protect Israeli security.
Despite numerous Israeli operations against it and clampdowns by Yasser Arafat's Palestinian National Authority, Hamas found it had an effective power of veto over the process by launching suicide attacks.
In February and March 1996, it carried out several suicide bus bombings, killing nearly 60 Israelis, in retaliation for the assassination in December 1995 of Hamas bomb maker Yahya Ayyash.
The bombings were widely blamed for turning Israelis off the peace process and bringing about the election of right-winger Benjamin Netanyahu, who was a staunch opponent of the Oslo accords.
In the post-Oslo world, particularly following the failure of US President Bill Clinton's Camp David summit in the summer of 2000 and the second intifada which followed shortly thereafter, Hamas gained power and influence as Israel steadily destroyed the infrastructure of the Palestinian Authority.
In towns and refugee camps besieged by the Israeli army, Hamas organised clinics and schools which served Palestinians who felt entirely let down by what they saw as a corrupt and inefficient Palestinian Authority dominated by its secularist rival, Fatah. After the death of Fatah leader Arafat in 2004, the Palestinian Authority was taken over by Mahmoud Abbas, a vocal opponent of attacks on Israel.
He viewed Hamas rocket fire, the militants' weapon of choice in recent years, as counterproductive, inflicting little damage on Israel but provoking a harsh response by the Israeli military.
Hamas's decision to stand in Palestinian parliamentary elections in 2006 was a major departure for the movement and has had a profound impact on the Israeli-Palestinian conflict.
Top figures said the move reflected Hamas's importance in the Palestinian sphere and the need for it to address failing political structures.
It did not, they insisted, imply any acceptance of a two-state solution to the conflict.
Aside from its much-vaunted incorruptibility, Hamas campaigned forcefully on its claim that Israel's withdrawal from Gaza in the summer of 2005 was a victory for its commitment to armed conflict with the Israelis.
But life in government has proved a hard challenge, for Hamas and for the long-suffering Palestinian people.
The government has been subject to economic and diplomatic sanctions by Israel and its allies in the West.
The embargo will remain, they say, until a Palestinian government is formed that is committed to past peace deals signed with Israel and which recognises Israel's right to exist – demands that Hamas has been unwilling to accept.
Rocket attacks against Israel by militants have continued and the organisation has vowed to carry out revenge attacks.
'The West should impose a ceasefire'
Analysis by Toby Kelly, senior lecturer at Edinburgh University specialising in the Israeli/Palestinian conflict
1. Why did Israel attack?
The main issue was the continued firing of Hamas rockets from the Gaza Strip into southern Israel. That's been going on since the Israelis left the Gaza Strip in 2005. It continued, albeit at a slower pace, during the recent six-month ceasefire which ended on Friday. When the ceasefire ended there was another spate of them.
The Israeli view was articulated by Israeli Prime Minister Ehud Olmert when he said yesterday: "Israel has done all it could to preserve the ceasefire with Hamas, but our desire for quiet was met with terror."
The Israelis would also argue that the capture of Gilad Shalit, an Israeli soldier held hostage by Hamas, had been a key factor.
There is also an Israeli election coming up and both of the main candidates, Benjamin Netanyahu and Tzipi Livni, have promised to end Hamas control in Gaza.
2. What will be the impact of the air strikes?
Despite the damage done, Hamas are not going to disappear. They will still be in control of the Gaza Strip, but they will be weakened. Some of their leadership could have been killed and they now have less capacity to launch rockets into southern Israel, which they have been doing intermittently but causing very few fatalities. There have been suggestions that Hamas wanted a renewal of the ceasefire, but that is now off the agenda for the short term.
3. Will Hamas retaliate?
It is difficult to see how they can. Militarily they are weak. We may see some headline-grabbing spectaculars launched from the West Bank, but in terms of their military resources they are not able to take on the Israelis in any way. In fact, Israel may decide to increase the pressure and go in by land. Even if they do this, I don't think they will be able to break Hamas. There are 1.3 million people on the Gaza Strip – they are still going to be there. This is unlikely to make them any less supportive of Hamas and, in fact, is likely to strengthen their support. This could draw Hamas-controlled Gaza closer together with the Fatah-controlled West Bank against Israel. To some extent it might bring some unity.
4. What should the West do?
In the short term, the West should call for a renewal of the ceasefire. I believe they should even impose a ceasefire, although they probably won't. The fact that Israel has control over many aspects of daily life in the Gaza Strip, even though the troops have withdrawn, means there are broader issues than just the here and now. These structural issues must be addressed.