Here is what we know so far about the terrorist attack at Manchester Arena that targeted young concert-goers.
::22 people, including many children, have been killed and 59 injured in the blast.
:: The attack was carried out by a lone male suicide bomber who detonated an improvised explosive device. He died at the arena.
:: Security services believe they know his identity and are investigating whether he acted alone or was part of a network.
:: A 23-year-old has been arrested in South Manchester in connection with the incident.
:: Islamic State has claimed responsibility for the attack.
:: The first victim has been named as college student Georgina Callander. Eight-year-old schoolgirl Saffie Roussos was also killed.
:: Speaking after chairing a Cobra meeting on Tuesday morning, Prime Minister Theresa May said the “callous” attack was “among the worst terrorism we have experienced in the United Kingdom”.
:: A vigil will be held at 6pm on Tuesday in Albert Square, Manchester.
:: The explosion took place at Manchester Arena as people began streaming from the doors after a show by American singer Ariana Grande.
:: Greater Manchester Police said they were called to the venue at around 10.33pm and approach roads were closed.
:: Manchester Victoria station was evacuated and trains cancelled until at least the end of Tuesday.
:: The injured - including 12 under the age of 16 - are being treated at eight hospitals across Greater Manchester, Chief Constable Ian Hopkins said.
:: President Donald Trump expressed his “deepest condolences” to the victims and branded the attackers “evil losers”.
:: Extra police officers have been put on duty in London in the wake of the attack, Metropolitan Police Commissioner Cressida Dick announced.
:: Andy Burnham, the Greater Manchester metro mayor, called the atrocity “an evil act”.
:: All national General Election campaigning was suspended after the explosion.
:: A controlled explosion was carried out on Tuesday afternoon, as part of the investigation, at an address in Fallowfield.