Four people were shot, one dead, at a T.I. concert at Irving Plaza late Wednesday night. View Full Caption DNAinfo/Noah Hurowitz

UNION SQUARE — A man died and three other people were injured, including a local rapper, when a feud between two performers' entourages erupted in gunfire in the green room of Irving Plaza during a T.I. concert Wednesday night, sources said.

Rappers Uncle Murda and Maino were performing on stage at 17 Irving Place, near East 15th Street, about 10 p.m. when the two crews started jostling in the third-floor green room and gunfire erupted.

A 33-year-old man was shot in the stomach, a woman in the leg, another man in the chest and a third man in the leg, according to Chief William Aubrey of the Manhattan South Detective Squad.

Two shots rang out and sparked pandemonium in the venue before the award-winning rapper T.I. was set to perform, said witness Kurt Elphage.

In one video posted to YouTube, T.I. can be seen hanging out backstage before sounds of gunfire send concertgoers scattering.

Ronald McPhatter, 33, was pronounced dead at Beth Israel Hospital, sources said.

Maggie Heckster, 26, was treated at Bellevue Hospital along with Christopher Vinson, 34, who was shot in the chest, sources said. They were both listed in stable condition, police said.

Roland Collins, 30, who performs under the name Troy Ave after the Crown Heights street he grew up on, also walked himself into a New York University hospital where he was treated for a gunshot to the leg, sources said.

Concertgoers quickly took to social media to to express their shock at the shooting and condolences to the victims.

(Warning: graphic language)

Tonight I attended TI's concert at Irving plaza. During the concert multiple people were shot, including a girl who was standing next to me. You never know when your life is going to be taken from you. Please pray for the people fighting for their lives tonight who are in critical condition. My thoughts go out to the victims families affected by this senseless act of violence A photo posted by LIV H (@yungliv_) on May 25, 2016 at 9:09pm PDT

Crazy shit shots fired in the building. Thank god me and my sis made it out. @troubleman31 never showed up for the concert. Very disappointed in @troubleman31. But i hope that everyone made it out ok. A video posted by Eli (@elijahamin) on May 25, 2016 at 8:13pm PDT

Another attendee at the venue, Rodney Molina, claimed there was no security and that no one had been patted down while entering.

"Irving Plaza should be held responsible," Molina said.

Police sources said it appears the gunman bypassed security.

Staff at Irving Plaza did not respond to requests for comments Thursday morning.

A photo posted by Irving Plaza (@irvingplaza) on May 25, 2016 at 10:19pm PDT

Police were still investigating the incident.

There were no arrests as of Thursday morning, police said.

— Reporting by Noah Hurowitz, Trevor Kapp, Murray Weiss, Radhika Marya and Aidan Gardiner