A policeman has been bitten by a police dog while searching for a man in Melbourne.

Officers on patrol came across two men and a woman on Cleveland Street at Ashwood about midnight and stopped to talk to them when one of the men ran off, prompting the search.

The dog squad was called and a constable copped a small bite from one of the canines.

He has since been released from hospital, while a man and a woman in their 40s are being interviewed.