The victim was found with stab wounds in Davenport Street, Bolton, on Saturday night and died at the scene.
Police said a group of attackers, wearing dark clothing, ran off when witnesses tried to help the man being attacked.
A 29-year-old man has been released from custody pending further inquiries.
A post-mortem examination has confirmed the man died from multiple stab wounds.
Detectives said they were following "a number of lines of inquiry" but urged people to contact them with information, "no matter how big or small".
A man who was arrested on suspicion of murder following the stabbing of a 39-year-old man in a street attack has been released on bail.