Police have released an image of the man they allege assaulted a security guard at a Civic bar last month. 

They say that at about 12.05am on July 26, the man allegedly assaulted a security guard at the One22 bar on Alinga Street before fleeing in the company of two other men.

The man is described as Caucasian in appearance, with a solid build, brown hair and beard, dark eyes, with sleeve tattoos down both arms.

He was wearing a light khaki green T-shirt and jeans at the time.

Anyone who can identify the man or who may have witnessed the alleged assault should call 1800 333 000 or via the Crime Stoppers ACT website.