Updated

A man fatally shot three musicians in Brooklyn before turning the gun on himself in a dispute over money, police say.

Two of the dead were brothers and members of the group the Yellow Dogs, who came to the U.S. from Iran three years ago after appearing in a film about the underground music scene there, according to band manager Ali Salehezadeh. Another person killed was also a musician but wasn't in the band, and a person wounded in the shooting was an artist, he said.

The shooter was a member of another band from Iran, the Free Keys, who knew the victims but hadn't spoken to them in months because of a "very petty conflict," Salehezadeh said, declining to give specifics.

"There was a decision not to be around each other," he said. "They were never that close to begin with. ... This was nothing. We thought it was all behind us."

Detectives suspect there was a dispute over money, but they were still investigating the motive and the relationships between the victims and the shooter, Police Commissioner Raymond Kelly said. Preliminary reports from police that the shooter had been a member of the Yellow Dogs but was kicked out were inaccurate, the manager said.

“[The shooter] stole money and possibly equipment, and he didn’t live up to his end of the bargain,” a law enforcement source told the New York Post earlier.

The four victims lived in a row house in East Williamsburg, an industrial neighborhood home to mostly warehouses where artists can rent cheaper space than in trendier parts of the city.

The rampage erupted shortly after midnight when the gunman opened fire through a window, then went inside and continued firing, Kelly said. Police found a 27-year-old man with a gunshot wound to the chest on the second floor. Two others were found shot in the head on the floor above, a 35-year-old and another whose age wasn't immediately known. A 22-year-old artist was wounded in the arm and was hospitalized in stable condition.

The gunman was found on the roof with a self-inflicted shot to the head, police said. An assault-style rifle was found next to the body. Kelly said it had been purchased in upstate New York in 2006 and police were investigating its history.

On their Facebook page, The Yellow Dogs describe themselves as a “psychedelic/Dance post Punk” group.

The Yellow Dogs played recent gigs in New York at indie rock venues like the Knitting Factory and Brooklyn Bowl, and their dance music sound is a little like Joy Division. Originally from Tehran, they were the subject of a 2009 film, "No One Knows about Persian Cats," which told the semi-fictional tale of a band that played illegal rock shows in Tehran.

A neighbor told the New York Post that the group would play in raucous parties inside their building, but were otherwise “very pleasant kids.”

“You can hear them playing their music on Friday night to Saturday nights. They sounded really good and it was never obnoxious like club music. These guys were playing real rock ‘n' roll,” Marcus Durant said.

“You always see them coming in and out of their house with their musical instruments in cases. They seemed like great kids, never bothered anybody,” added Martin Greenman, a 63-year-old metal worker who lived in the area.

The band came to the United States to pursue its dream of playing rock music in an open society, Salehezadeh said.

"You can't be a rock star in Iran," he said. "It's against cultural law. You can't grow there as a band."

The two members who were killed were a guitarist and a drummer who had just received political asylum. The bass player and singer weren't home at the time of the bloodshed and weren't harmed.

Salehezadeh spent the morning on the phone speaking to the victims' relatives, who were stunned by the violence.

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The Associated Press contributed to this report.