The incident happened around 3.20am on Saturday 22 December in Restalrig Road South near the roundabout with Sleigh Drive.
A 48-year-old man had just got out of a taxi when he was approached by a group of youths, three male and one female. Two of the group demanded money.
He was punched to the head and body, knocked to the ground. When he tried to get up he was assaulted again and sustained serious facial injuries.
The group then walked off westward towards Sleigh Drive, having taken a sum of cash from the man’s pockets.
Officers are seeking helping in tracing a number of suspects. The first male is described as white, aged 17 to 20, five feet seven inches tall, with a local accent and wearing blue jeans and a black jacket.
A second is described as white, aged 16 to 19, five feet five inches tall, of slim build, with short, dark hair and wearing a blue jacket. There is no description of the third male.
The female is described as white, aged 16 to 19, white, of medium build, with a local accent and wearing a white or light coloured jacket.
Detective Sergeant Gavin Howat of Gayfield Police Station said: “This was a vicious attack and we are appealing to anyone who was in the area at the time who can assist with our inquiries to get in touch.
“In particular we would like to speak to any taxi or private hire drivers who may have been seen the attack or who may have dash-cam footage that will help us establish what happened and trace those responsible.
“Anyone who saw something or who may have information is asked to contact Police Scotland on 101 and quote incident 0910 of 22nd December, or make a call anonymously to the charity Crimestoppers on 0800 555 111.
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