Police were talking to witnesses and reviewing evidence, trying to learn more about the fighting that led to the gunshots early Sunday morning.
"We believe it was a dispute between two neighborhoods that led to violence at the event. In no way was the event the target, it just happened to be the forum for the shooting," Mercer County Prosecutor Angelo Onofri told ABC News Sunday afternoon.
Onofri praised the quick thinking of the officers who responded to the shooting at the Roebling Wire Works Building, where he said 22 people were injured and 17 were shot.
Earlier Sunday, Onofri said officials believe an officer shot and killed the suspect. The Mercer County's Prosecutors Office Homicide Task Force has taken over the investigation due to the officer-involved shooting.
"Clearly the impetus for the police returning fire was the individuals shooting at each other," he said. "Frankly, if it wasn't that type of response, I think we would be talking about more victims."
Of the 17 people treated for gunshot wounds, including a 13-year-old boy, only one person, a suspect, remained in critical condition Sunday night, said Onofri.
The number of injured rose from 20 to 22 after Onofri announced two more victims arrived at area hospitals. He said a male victim suffered a grazed gunshot wound. A female victim was hiding behind a vehicle. When the driver of the vehicle took off, she was thrown and sustained bruising to her scalp.
"It absolutely could have been worse given the confined space and the number of shots that appeared to have been fired," Onofri said.
The shooting happened around 2:45 a.m. Sunday at the 'Art All Night Trenton 2018' festival at the Roebling Wire Works Building on the 600 block of South Clinton Avenue.
Officials said a dispute between neighborhood gangs is believed to be what led to the violence. They say the event was on the verge of being shut down when gunshots rang out.
"Prior to the shooting, members of the Trenton Police Department informed event organizers that the event needed to be shut down," Onofri said. "There was a report that the mood inside the venue had been changing."
Onofri says multiple individuals who were attending the event opened fire in the venue. Several weapons have been recovered.
One witness said everything unfolded very quickly.
"All of the sudden, inside the doorway about 10 shots went off. Like pow, pow, pow, pow, pow, pow, pow... and everyone started running," said Edward Forchion.
Authorities have identified two suspects in the shooting. Tahaij Wells, 33, the suspect who was killed, had recently been released from prison and was on parole since February on homicide-related charges, Onofri said. Another suspect, 23-year-old Amir Armstrong, remained hospitalized in stable condition and was charged with a weapons offense. It was not immediately known if he had an attorney who could comment. A third suspect remained in critical condition.
They say there could be more suspects and are questioning witnesses.
VIDEO: Aftermath of Trenton arts festival shooting
Irving Higginbotham was one of those injured. He told Action News he was shot four times.
"Everybody was having a nice time. The next thing you know, there were gunshots, got shot in the leg, fell on the ground, and that was it," Higginbotham said.
Trenton resident Angelo Nicolo spoke to Action News about what he witnessed.
"And 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. All hell broke loose," Nicolo said.
Nicolo said he saw one person with a gunshot wound to the leg.
"I saw two police officers escort a guy that got shot in the leg; they bandaged him up and whisked him away before the ambulance came here. It was pretty gnarly," Nicolo said.
Trenton fire crews as well as medics, including some from Bucks County, were called to the scene. The ATF is also assisting with the investigation.
Officials are also investigating reports of an attempted carjacking that occurred nearby. They say a man approached three people in a vehicle in the aftermath of the shooting. At the time, officials say, the man may or may not have pointed a gun at the people in the car. The vehicle sustained some damage. Authorities have not released any further details in this incident, and are looking into whether it is connected to the arts festival shooting.
The 'Art All Night Trenton 2018' event started at 3 p.m. Saturday and was scheduled to run until 3 p.m. Sunday. The festival showcased 1,500 pieces of local art, live murals, live art instructions and 60 plus musical acts performing on three stages.
Officials say approximately 1,000 people were in the area at the time of the shooting and there were no metal detectors at the building.
'Art All Night Trenton' organizers posted their reaction to the shooting on social media:
"It's with great regret that we announce that the remainder of Art All Night has been canceled due to a tragic incident that occurred overnight.
We're still processing much of this and we don't have many answers at this time but please know that our staff, our volunteers, our artists and musicians all seem to be healthy and accounted for. Our sincere, heartfelt sympathies are with those who were injured.
We know there are a lot of questions and a lot of speculation at this point. We're still trying ourselves to piece this entire situation together. What we do know is that we are currently unable to release any submitted artwork that is currently inside the Roebling Wire Works building. That being said, we promise you we'll be in touch as soon as we have more questions we information on this. We truly appreciate your understanding and patience during this incredibly difficult and confusing situation.
We're very shocked. We're deeply saddened. Our hearts ache and our eyes are blurry but our dedication and resolve to building a better Trenton through community, creativity and inspiration will never fade. Not tonight. Not ever."
While the investigation continues, those that work in the building where the festival was held are trying to figure out how to move forward Monday.
Zoe Brookes runs a non-profit for at-risk Trenton youth headquartered in the Roebling Wire Works Building.
"The normal thing for us to do is to reclaim our office at noon," she said. "There's no playbook for this. I'm figuring my way through it, looking to partners in the city to help guide and look together for healing."
The Associated Press contributed to this article
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