The Brooklyn man fatally shot backstage at Irving Plaza Wednesday night was facing an attempted murder charge in a shooting at a different Manhattan club last November, court records show.

Ronald McPhatter, 33, was killed and three others wounded when gunfire erupted at Irving Plaza, where Grammy Award-winning rapper T.I. was getting set to perform, the NYPD said. The killer is being sought.

NYPD Commissioner William Bratton said Thursday that the culture surrounding the “gangsta rap world” creates the atmosphere that led to the fatal shooting.

McPhatter was shot in the stomach and later pronounced dead at Mount Sinai Beth Israel Hospital in Manhattan, police said.

He was arrested last year on charges of attempted murder and weapons possession stemming from a Nov. 17 shooting at the club Pergola, records show. The case was slated for another court appearance next month.

NYPD detectives recovered five gun shells inside Irving Plaza near the green room where dozens of VIP guests were caught in the crossfire of two warring groups tied to rappers who were performing at the time, police said.

Police said no one associated with T.I. was involved in the shooting.

advertisement | advertise on newsday

“It started as fisticuffs for about five minutes” before shots were fired, said NYPD Chief of Detectives Robert Boyce.

Four of the gun shells came from the same gun, Boyce said. A gun has not been recovered and the shooter is still at large.

“We have significant video and strong leads,” said Boyce, adding that witnesses have been cooperating with investigators.

Police said there were about 950 people inside rushing to get out of the hall when the shots rang out. Concertgoers were forced to use a narrow staircase to flee the scene.

Boyce said he could not comment on how a gun was brought inside the music venue despite a metal detector that was used to scan concertgoers.

Bratton told CBS 880 radio Thursday morning that investigators “have a pretty good idea of what happened . . . We should be able to wrap it up very quickly.”

Law enforcement officials said the shooting occurred in the third-floor green room, an area where talent waits before going onstage.

Bratton on CBS called rappers “talented artists” but said they “celebrate the drug culture and the denigration of women.”

He called the scene surrounding the rap world “crazy,” describing it as “basically thugs who celebrate violence.”

A representative for T.I., who went to prison in 2009 on federal gun charges and after being released to a halfway house was found to have violated parole in December 2010 and was sentenced to 11 months, referred all questions to police.

advertisement | advertise on newsday

Police said metal detectors were set up at Irving Plaza, a 1,025-person ballroom-style music venue, but witnesses said security getting into the concert was lax. On a message posted to its official Twitter account, Irving Plaza officials wrote: “Until we have further details about what transpired, we are referring all inquiries to the NYPD.”

Police Thursday morning had the front entrance of the concert hall closed off with police tape. An NYPD Crime Scene Unit van was parked outside with several police officers standing guard to keep pedestrians off the sidewalk.

Chief of Manhattan Detectives William Aubry said the shooting erupted while Brooklyn rappers Maino and Uncle Murda were performing ahead of the scheduled show by T.I., a rapper and actor whose real name is Clifford Joseph Harris Jr. T.I.’s work has featured appearances by a host of well-known stars, including Rihanna, Iggy Azalea, Justin Timberlake and Eminem.

Police said that while Maino, who’s from Bedford-Stuyvesant and whose real name is Jermaine Coleman, and Uncle Murda, who is from East New York and whose real name is Leonard Grant, were onstage, a backstage dispute involving the rappers precipitated the shooting at about 10:15 p.m.

The victims included a 30-year-old man and a 26-year-old woman, each of whom was shot in the leg; a 34-year-old man who was shot in the chest; and the 33-year-old man who died, the NYPD said in a statement Thursday. Police said the woman and the 34-year-old man were transported by ambulance to Bellevue Hospital Center in stable condition. The 30-year-old man was taken by private means to NYU Langone Medical Center, where he was treated, police said.

advertisement | advertise on newsday

There have been no arrests.

The concert venue is on Irving Place between East 15th and East 16th streets, not far from Union Square Park in lower Manhattan. Witnesses described a frantic, frightening scene inside the venue, as reported by The Associated Press.

Live Hoffman, 19, told the AP she was in the balcony VIP area to the left of the stage when the shooting occurred.

She said an argument between two groups of people precipitated the shooting and that she had been talking with the female shooting victim before gunfire erupted in the concert hall.

“The girl next to me was shot point-blank, and men picked her up and carried her out,” a shaken Hoffman told AP. “For two to three minutes we still heard firing, still heard shots, we were clutching each other making sure no one was getting hit.

“I ran out,” she said, “just trying to look for my friends, just trying to see if everyone was OK. Everyone was hysterical.”

Elijah Rodriguez told the AP he also was in the VIP area by the stage and that T.I. was supposed to go on before 9:30 p.m., but “he never showed up.”

The NYPD chief of Manhattan detectives, Aubry, said T.I. was in the building, but that the rapper hadn’t taken the stage because Maino and Uncle Murda were still performing. After he was to perform at Irving Plaza, T.I. was scheduled to perform at the 1OAK nightclub on West 17th Street. A reference to that show has since been deleted from the official 1OAK NYC website and a link to its Twitter account said simply that the posting no longer exists.

Rodriguez, the concertgoer, told the AP: “It was scary to deal with. When I got outside, like literally across the street, there were a few girls having, like, panic attacks. One girl thought she saw someone get shot in front of her.”

With Gary Dymski, John Valenti and Anthony M. DeStefano