Neighbors in Plymouth are making frightening discoveries in their yards and nearby parks -- homemade soda bottle bombs.
Police think the bomb makers are amateurs, but their handy work could end up seriously hurting someone.
So far, police say seven homemade bombs have gone off in parks and lawns this summer, six in just the last couple weeks.
"What concerns us is the danger," said Plymouth Police Department Deputy Chief Dan Plekkenpol. "I don't' know if they're really realizing the fact that they could get second- and third-degree burns when these bombs go off."
These bombs are usually made with plastic soda bottles and common household cleaners. A chemical reaction sets off the explosion, sending debris flying.
One other factor is the bombs don't always explode right away, and if they're left out in the open, police worry someone could get seriously hurt.
Investigators say it looks like teenagers are to blame for the bombs. It might be their idea of a prank, but neighbors aren't laughing.