BALTIMORE (AP) — Authorities have arrested and charged a teen who detectives believe was involved in a shooting at a Baltimore block party over the holiday weekend that left two people dead and 28 others wounded, officials announced Friday.

Members of the homicide and SWAT teams arrested the 17-year-old boy around 7 a.m. Friday after a search warrant was executed at a home, police said in a news release. He was taken to the Central Booking Intake Facility, where he was charged with possession of a firearm by a minor and possession of an assault weapon, as well as reckless endangerment and having a handgun in a vehicle, police said.

Police referred to the teen in the release as a person of interest. He is charged as an adult, but police aren’t identifying him since he is a minor, according to department spokesperson Detective Freddie Talbert.

Detectives are still actively investigating the shooting in the Brooklyn Homes area in the southern part of the city, Talbert said. A reward for up to $28,000 is being offered for any information that leads to an arrest and charges in the case.

There was a wave of shootings this week as the U.S. celebrated the Fourth of July. The gun violence that flared this week in Washington, D.C.; Louisiana; Florida; Pennsylvania; Texas; Maryland and Massachusetts left more than a dozen dead and more than 60 wounded — including children as young as 2 years old.

Earlier this week, interim Baltimore Police Commissioner Richard Worley said that investigators believed there were multiple shooters in the block party shooting, and that it wasn’t clear if the shooting was targeted or random.

“We don’t know exactly how many, but we do know more than one person was shooting,” Worley said. The event has been held for decades, but no permit was issued this year and police didn’t find out about it ahead of time, as they have in past years, Worley said.

Police identified the two people killed as 18-year-old Aaliyah Gonzalez and 20-year-old Kylis Fagbemi. The 28 injured victims ranged in age from 13 to 32, with more than half younger than 18, officials said. Of those injured, police said Friday that three victims remain at hospitals in fair condition.