The alleged assault occurred at around 9pm on the evening of Thursday 14 March on the number 21 Lothian Bus service to Clovenstone.
A disturbance broke out on the upper deck of the bus as it was travelling along Ferry Road.
Wishing to remain anonymous, an eyewitness, who boarded the bus near Crewe Toll, said one of the aggressors threatened to hit a woman in their group “like a man” before proceeding to punch her in the face.
“There was a lot of swearing and shouting, there were kids on the bus. It was shocking,” the eyewitness told the Evening News.
“The fighting was happening on the upper deck of the bus then quickly escalated and moved downstairs. It looked as if the group had just come back from a funeral or wake.
“One of the men was shouting at a woman and threatened to punch her like a man. Then he did. It was totally out of order.”
The eyewitness said the bus remained static at this point near the Morrison’s supermarket on Ferry Road, with the police arriving shortly afterwards.
“I believe it was a domestic, as the woman did not want to press charges when the police arrived,” the eyewitness added.
A spokesperson for Police Scotland confirmed officers attended a bus disturbance on Ferry Road, which was reported at 5 past 9.
They added that no complaints of an assault were made and that nobody was arrested.
Lothian Buses have been approached for comment.
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