Two teenagers have been arrested following reported chemical explosions at a Dollar Tree store and softball field in Brewer.

Police and fire officials responded to a reported chemical explosion at the Dollar Tree in the Twin City Plaza on State Street on Sunday around 7:30 p.m. The store had been evacuated because of reports of what sounded like gunshots and a strong chemical smell, Brewer police said in a statement.

Investigators said the explosion was caused by a chemical device that was intentionally placed there.

Officials discovered similar devices were also set off at the Brewer High School softball field, according to police.

The two teens, who police are not identifying, were taken to Long Creek Youth Development Center in South Portland.

According to police, the pair had previously thrown large rocks off an interstate overpass, one of which went through the windshield of a car driving on Interstate 395. The teens were also previously charged with assault, reckless conduct, violation of release conditions and were currently on house arrest.

The Fire Marshal’s Office is still investigating the incident at the Dollar Tree, police said.