Police have begun a murder investigation after tests revealed a man found dead in flats in Bedford had suffered a stab wound to the neck.
Inderjit Singh, 39, of Bedford, was discovered in Calshot Walk in the early hours of Christmas Day.
He is known to have knocked on several doors in the area on Christmas Eve, police said.
A man arrested by police has been released on bail.
Det Ch Insp Steve Collin said: "We are keen to hear from anybody in Calshott Walk or the nearby vicinity that may have seen Mr Singh in the area between 1700 GMT on 24 December and 0200 GMT on 25 December."