The 37-year-old man was walking down Princes Street towards the East End at around 10.35pm on Monday 23 July, when he challenged a group of of six or seven teenage boys who were hassling members of the public at a bus stop opposite Marks and Spencer.
The youths attacked the victim, resulting in him sustaining a number of serious injuries to his face. He was taken to Edinburgh Royal Infirmary for treatment.
Officers are now asking anyone who can assist with their inquiries to come forward.
The suspects are described as being around 15 or 16-years-old and wearing dark puffer-style jackets. One of the youths had blond hair.
Detective Constable John Dunn from the Violence Reduction Unit at Gayfield Police Station said: “The victim has attempted to come to the aid of a number of people who were being intimidated by the group of suspects. His intervention subsequently resulted in a vicious attack that left him requiring medical attention.
“We would urge anyone who was on Princes Street on Monday evening and witnessed this assault to contact police immediately.
“In particular, we would like to speak with the members of the public who were being hassled by the group and who may be able to provide us with more information that can help identify these youths.”
Those with information can contact the VRU via 101 and quote incident number 4535 of the 23rd July. Alternatively an anonymous report can be made to the charity Crimestoppers on 0800 555 111.
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