LIVERMORE FALLS – A Livermore Falls High School student was suspended after pulling a prank on a field trip to the Greater Boston area.

Officials say the student hung a sign in the back window of the bus saying, “Help, we’ve been kidnapped.” A motorist saw the sign and called police.

Bus driver Don LeSuer, unaware of the prank, had just dropped off two dozen students and was looking for a parking space in Arlington, Mass., when eight police cruisers pulled up and officers surrounded the bus. One of the officers asked LeSuer if he was aware that someone had called police alleging a kidnapping.

LeSuer thought the officer was kidding but he wasn’t. The officer went to the back of the bus and returned with the sign. “He told me, ‘Unfortunately, you are the subject of a prank,”‘ LeSuer said.

The student responsible for the “inappropriate” sign has been suspended from school for 10 days and has been barred from riding a school bus indefinitely, Principal Rod Wright said.

Wright said he was waiting for the bus when it returned Friday afternoon from the field trip to the Museum of Fine Arts in Boston.

“The student thought it was a prank, but it turned out to be not so good of a prank,” Wright said. “Unfortunately, students don’t realize what the ramifications of a prank like this could be.”