A man has been rushed to hospital in a critical condition after being brutally attacked in the early hours of Sunday.

Police say the 27-year-old from Seaford was approached by a group of strangers on King Street around 4.30am.

The men hit him over the head with a weapon, seriously injuring him. He remains in a critical condition at the Royal Melbourne Hospital.

Detectives believe the group was travelling in two vehicles, a red Subaru and a red Mitsubishi. Police are appealing for anyone with dashcam footage around the time of the attack to come forward.