An unknown number of gunmen opened fire at the Art All Night Trenton 2018 festival Sunday morning and injured up to 20.

One person, believed to be one of the gunmen, was killed at the at scene.

The Princeton Patch reported that police responded to emergency calls around 2:50 a.m. to discover “multiple males at the event shot multiple people attending.” Witnesses describe a scene in which the suspects were “squaring up” against each other.

The Mercer County Prosecutor’s Office (MCPO) the “suspects were wounded by the time police arrived on scene.”

A 33-year-old suspect was killed at scene. The Straits Times reported that police recovered multiple firearms from the scene and a second suspect was arrested.

The festival was held in the Roebling Market area. The Trentonian reports that “Roebling Market parking lot was covered in trash, broken glass and liquor bottles Sunday as police processed the scene for evidence.”

AWR Hawkins is an award-winning Second Amendment columnist for Breitbart News, the host of the Breitbart podcast Bullets with AWR Hawkins, and the writer/curator of Down Range with AWR Hawkins, a weekly newsletter focused on all things Second Amendment, also for Breitbart News. He is the political analyst for Armed American Radio. Follow him on Twitter: @AWRHawkins. Reach him directly at awrhawkins@breitbart.com. Sign up to get Down Range at breitbart.com/downrange.