A man was hospitalised after being attacked in a Brighton park on Tuesday (May 15), police said.
The 24-year-old man from Benfleet, Essex, was visiting the city when he was assaulted, police said.
Officers said the victim as sitting in East Brighton park, at some time between 4pm and 4.20pm, when he was assaulted by two white men, both in their late teens.
Both men are described as around 5ft 6, and one had short fair hair and was wearing a white t-shirt and shorts, while the other had brown hair and was wearing sunglasses.
Police are now appealing for witnesses to the attack.
Detective Constable Melanie Down said: “This was a vicious and unprovoked attack on a visitor to the city. He suffered a fractured cheek bone which required hospital treatment.
“I’d ask anyone who saw what happened or who helped the victim after he was attacked to come forward.”
Anyone with information should contact police online or phone 101, quoting serial 47180067090.
Alternatively, call Crimestoppers anonymously on 0800 555 111.