NEW CUMBERLAND, Pa. (AP) — Tipsters have helped identify two suspects in central Pennsylvania accused in a string of incidents over the past month where rocks have been thrown at vehicles from an interstate overpass.

Six vehicles have been damaged by the rocks in four incidents since Oct. 1, police said. One minor injury was reported, but the victim did not need medical treatment.

The juveniles were identified by midday Friday, after Pennsylvania State Police asked for the public’s help identifying them.

Police said the suspects and their families are cooperating with the investigation. Their names were not released.

The incidents at the Pleasant View Road overpass of Interstate 83 near New Cumberland occurred between 11 p.m. and 1 a.m., police said.

In one case, a victim was driving southbound on I-83 about 8 miles (13 kilometers) south of Harrisburg on Oct. 21 when a softball-sized rock crashed through the windshield, nearly hitting someone.