PAWTUCKET — The suspicious-looking object that forced the evacuation of Tolman High School on Thursday wasn’t a pipe bomb — it was part of a pipe organ.

Tolman Principal Frederick W. Silva said yesterday that a couple of students had pried the pipe loose from the school’s circa 1927 pipe organ, which was walled off in a recent renovation of the high school auditorium and forgotten.

Tolman’s 1,300 students were sent home and the state fire marshal’s bomb squad was called in after a teacher spotted the object in a second-floor locker and alerted school officials.

Bomb squad members couldn’t figure out what the object was. They destroyed it as a precaution, applying a small explosive charge.

Because the detonation wasn’t followed by a bigger explosion, officials concluded that the object probably wasn’t a bomb. But because it looked so sinister, Pawtucket police officials asked the federal Bureau of Alcohol, Tobacco and Firearms to get involved, handing the fragments over to a BATF agent late Thursday afternoon.

Silva said school officials learned the object was part of Tolman’s decommissioned pipe organ when the two students who took it confessed, saying they had stuck the object in the locker for safekeeping.

“At this time, we are convinced that this was a case of stealing and an attempt to conceal contraband and not an attempt to stage a bomb hoax,” he said in a letter sent home to parents yesterday.

The students, both boys, have been suspended for 10 days, Silva said.

Their motive for taking the pipe organ part?

“What they found out was they could make noises by blowing up into it,” Silva said.

jcastell@projo.com