A man was gunned down while apparently trying to break up an early-morning fight Monday in an alley just feet from a downtown Minneapolis police station, and a second man was seriously injured in the same shooting, police and community activists said.

Officers on patrol as area bars were closing heard gunshots and went to the alley between Hennepin Avenue and N. 1st Avenue, behind the Gay 90's bar and around the corner from the Minneapolis Police Department 4th Street station, where they found the victim, police spokesman John Elder said.

Friends and relatives on social media identified the victim as Michael Clark of Minneapolis.

Clark and his girlfriend had just left Auggie's Cabaret when they spotted a man — believed to be Clark's nephew — fighting with another man, said Jamar Nelson of A Mother's Love, a violence-prevention group that patrols downtown during the summer months.

"He jumped out of the car to go assist his nephew in the fight, and [his girlfriend] heard gunshots after that, and saw Michael hit the ground," Nelson said. "That's how quick the fight was."

He said that he didn't know what sparked the argument between the nephew and the alleged shooter.

Elder said that moments after the shooting, people were seen running from the scene. A witness pointed out the shooter to officers, who ran after the suspect. Officers arrested a man in his 30s. The suspect was booked into the Hennepin County jail on probable-cause murder, where he remained held without bail Monday afternoon.

The victims were taken to HCMC, where Clark died. The second victim was in serious condition, Elder said.

It was the city's 13th homicide of the year.

Hours after his death, remembrances and tributes began popping up online for Clark, whose own Facebook page, which says the Chicago native was self-employed, reveals little about his personal life.

Police were continuing to investigate Monday and were processing evidence collected at the scene.

Anybody with information is encouraged to call CrimeStoppers at 1-800-222-8477. Tips may also be submitted electronically at crimestoppersmnm.org.