Six Barron High School students were arrested Friday and may face felony charges for possession of an explosive device. Officials say a caller phoned in a tip that led to the arrests.
Sheriff Tom Richie also believes there was no malicious intent behind the bombings.
"I believe they were (building and using the bombs) unfortunately for entertainment purposes, and I believe it just got carried out of hand," says Richie.
Seventeen-year-old Jesse Holmstrom, Bryan Mueller, Collin Mau, and twin brothers Shawn and David Hilbert, and a 16-year-old built the bombs from metal pipes and fuses, which exploded a short time after they were ignited, say officials.
Investigators expect to turn the case over the District Attorney's office Tuesday.