Google Maps(TRENTON, N.J.) — At least one person is dead and 20 injured after a wild shootout at a 24-hour art event in southern New Jersey early Sunday.

The shooting broke out at about 2:45 a.m. in Trenton, New Jersey, at Art All Night, an annual event to “promote artistic diversity by fostering creativity, learning and appreciation of the arts,” according to the event’s website. The event, held at Roebling Market in the southern part of the city, which lies just across the Delaware River from Pennsylvania, was attended by an estimated thousand or more people, authorities said.

The Mercer County prosecutor’s office said at a Sunday morning press conference that the one person killed, a 33-year-old man, is a suspect in the shooting. Another suspect is in custody.

Of those injured, 16 were treated for gunshot wounds and four for other types of injuries, said Mercer County Prosecutor Angelo Onofri.

Multiple people opened fire in the shooting and multiple weapons have been recovered, authorities said.

“It absolutely could have been worse given the confined space and the number of shots that appeared to have been fired,” Onofri said.

ABC station affiliate WPVI-TV in Philadelphia reported that “numerous people” were struck by gunfire and several ambulances were called to the scene to assist the injured. The Trenton Fire Department and police also responded.

Eyewitness Angelo Nicolo told WPVI-TV, “All of a sudden, my brother goes to me, ‘You hear that gunfire?’ I go, ‘It sounds like fireworks.’ He said, ‘No, that’s gunfire.’ Next thing you know, we turn around and everybody’s running down the street.”

Capital Health Systems, which operates Capital Health Regional Medical Center in Trenton, said numerous victims were being treated. The director of public relations at the hospital said they would not release numbers or conditions until all families were notified.

Authorities said at least one of those being treated was in “extremely critical” condition.

The Mercer County Prosecutor’s Office homicide task force is taking the lead in the investigation.

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