Police say they have opened a second-degree murder investigation after an unprovoked assault in a Kalihi bar  led to the death of a 26-year-old man.

According to police, the victim was punched in the face by another man, causing him to fall backwards. The victim was knocked unconscious when the back of his head hit the ground. The incident occurred around 2:05 a.m. Sunday.

Emergency Medical Services personnel took the victim to the Queen’s Medical Center, where his condition deteriorated. He was pronounced dead at 3:11 a.m.

Police identified a 21-year-old man as the suspect but no arrest has yet been made.