A 24-year-old man was within Kirkintilloch Skate Park when he was assaulted by a man with glass bottle at around 8.15pm on Saturday, June 26.
The victim was then chased towards Waverley Park by a group of men where he was assaulted further.
The 24-year-old was taken to Glasgow Royal Infirmary and treated for his injuries.
The suspect is described as wearing dark clothing.
Detective Sergeant Craig Paterson from Kirkintilloch CID said: “The skate park was busy at the time of this assault and I would appeal to anyone who witnessed what happened, or noticed the subsequent incident in Waverley Crescent, to please get in touch.
“Anyone with information is asked to contact Police Scotland through 101, quoting incident number 3373 of Saturday, 26 June, 2021. Alternatively you can call Crimestoppers anonymously on 0800 555 111.”