The incident happened at about 10:10pm on Saturday, April 20th in the town’s High Street.
In a statement, police said: “Officers received reports of a disturbance and on attendance a 22-year-old man was found with significant facial injuries. He was taken to the Edinburgh Royal Infirmary for treatment.”
Police said the victim was attacked by a group of around 15 people and have appealed to anyone who can help in identifying these individuals to come forward.
Detective Constable James Welsh, from Lothians and Scottish Borders CID, said: “This has been quite a large disturbance that left the victim with a number of painful injuries to his face.
“North Berwick High Street was likely to have still had a number of people coming and going from the area at this time of the evening and anyone who saw what happened and has yet to contact police should do so immediately.
“In addition, anyone who can provide any information that can help us identify those responsible is also urged to get in touch.”
Those with information can contact Lothians and Scottish Borders CID via 101 and quote incident number 5532 of the 20th April.
Alternatively, an anonymous report can be made to the charity Crimestoppers on 0800 555 111.
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