A man was punched in the face in his own home during a bizarre late-night break-in in Dandenong.
Greater Dandenong CIU Detective Sergeant Nick Lamb said a group attended the Wilma Avenue home about 12.55am on Saturday 10 February.
He said the group was described as three to four men and one woman, all of African appearance and aged in their twenties.
They entered through an unlocked front door, confronted the victim, 46, and punched him in the face.
Det Sgt Lamb said he suffered a suspected broken jaw and was taken to Dandenong Hospital.
He said the victim told police he did not know his attackers. They fled on foot without taking anything.
He said a number of other people were inside the house at the time, but they were not assaulted.
Det Sgt Lamb urged anyone with information to call Crime Stoppers on 1800 333 000.