A 20-year-old Michigan man bludgeoned his aunt to death with an exercise dumbbell during an argument Monday, police said.

The unidentified suspect, who sparked a 90-minute manhunt after jumping out a second-floor window, was arrested at a nearby golf course in Troy at about 4 p.m. The body of his aunt was discovered in the basement of a Shoreline Avenue home earlier in the day, Troy police Capt. Bob Redmond told The Post.

It wasn’t immediately clear what led to the brutal killing, the city’s first homicide since 2016, Redmond said.

“It was a kind of out-of-the-blue occurrence between him and his aunt,” Redmond said of the dispute. “There was nothing to indicate that this was going to happen. It just happened.”

Redmond said the suspect — who was expected to be arraigned Wednesday — used a dumbbell to attack his aunt. Officials could not say who owned the equipment or what size weight was used in the attack.

The suspect fled the home after allegedly beating his aunt to death and ran to a house next door. Three nearby homes are owned by relatives of the victim and the suspect, Redmond said.

Redmond said the killing rocked many residents in Troy, a northern suburb of Detroit.

“It’s rare for us to have here,” he told The Post. “It’s a big story in Troy because we don’t usually have them and this one is a family-related killing.”

The suspect and his aunt lived together at the same home. He remains in custody at a jail in Troy, the Oakland Press reports.