UPDATE: Police are looking for a gang which is believed to have attacked three people during a crime spree in Perth’s northern suburbs on Thursday night.

The first assault happened at about 7pm when a man in his 30s was approached by a large group of people in Central Park, just off Grand Boulevard in Joondalup.

The gang demanded he hand over alcohol and punched him in the head when he refused.

The victim was further assaulted as he lay on the ground. The man was taken to Joondalup Health Campus with a suspected broken jaw but he discharged himself after doctors found he had only facial swelling.

At about 8pm another man in his 30s was also attacked by a large group of people in Central Park after refusing to hand over his wallet.

He was punched to the ground and assaulted by before his wallet was stolen.

At 8.30pm a teenage boy was assaulted as he was boarding a bus at the Joondalup Train Station.

The boy was pulled backwards, thrown on the ground and assaulted by a group of people.

He was also taken to Joondalup Health Campus.

Police want anyone who saw the attacks or who might have CCTV vision of a group in Joondalup to call Crime Stoppers on 1800 333 000 or to make a report online at www.crimestopperswa.com.au