SHAWANO, Wis. (AP) — A Wisconsin teenager has pleaded no contest to charges that he triggered a bonfire explosion that injured more than a dozen people in 2022.

Sam Armstrong, 18, pleaded no contest on Monday to 13 counts of injury by negligent use of an explosive. A judge set his sentencing for April 11, WLUK-TV reported.

Under Armstrong’s plea agreement, prosecutors will recommend five years of probation and six months in jail, while his attorneys will be free to argue for whatever sentence they deem appropriate, said Shawano County District Attorney Greg Parker.

An attorney for Armstrong declined to comment Tuesday on the pending case.

Armstrong was attending a bonfire on Oct. 14, 2022, with other teenagers in the Pulaski area when he threw a barrel containing a mix of gasoline and diesel into the fire, sparking an explosion that burned at least 17 of the roughly 60 youths who were there, authorities said.

Armstrong, who was 17 at the time, told police he didn’t know his actions would cause an explosion and injure anyone, according to a criminal complaint. Armstrong told investigators he had been drinking beer.

He faces several civil lawsuits filed by some of the people who were injured in the explosion in someone’s backyard about 25 miles (40 kilometers) northwest of Green Bay.