UPDATE---

Sheriff Leo Dutton said on Tuesday afternoon that a transient had left a bottle of nuts and bolts wrapped with tape on the Rossiter School playground.

It was not an explosive device.

Authorities did evacuate the school and put all the other Helena schools in lock down as a precaution.

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Helena, state and federal authorities descended on Rossiter School early Tuesday morning when an improvised explosive device was found on the school’s playground.

Lewis and Clark County Sheriff Leo Dutton described what happened.

“Rossiter School had found a device that we believe was an already exploded improvised device,” said Dutton. “It was the size of a pop bottle wrapped with some tape. We’re not disclosing the contents of it right now. It was discovered just before 8:20 a.m. They recognized that it had already been exploded, but not this morning.”

Dutton said various authorities were called in to assist his deputies.

“They cordoned it off and immediately called law enforcement,” he said. “We responded with our bomb detection team along with ATF and FBI also on scene. They are processing the crime scene now. What remains to be done is looking for any video evidence, talking with neighbors, trying to find a witness and trying to find out why this happened.”

Dutton said all the schools in Helena were contacted.

“Other schools have been visited either by deputies or other law enforcement to do a search of the area for anything similar, and there was not,” he said. “Rossiter School was immediately evacuated to an area just east of the school that had been swept for safety. Buses were brought in, parents were notified and that was very orderly. We’re just trying to find out why this happened.”

Dutton said there were no warning calls to law enforcement or the schools in the area before the device was found.

“We were not called about it, there weren’t any threats,” he said. “We do want to say that all the schools are safe, they are no longer in lockdown. Rossiter School is done for the day, and the rest of the schools are back to business as usual.”

Dutton said there were no injuries, and there were no witnesses so far as to when the device was originally detonated, and he asks anyone in the Missoula area that may have any knowledge about this incident to contact 9-1-1.

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