An "improvised explosive device" was detonated at an elementary school playground in Montana Tuesday. No injuries have been reported.

Per NBC Montana, no one was hurt when the device was detonated at the Rossiter Elementary School playground in Helena. Local authorities have clarified that "no threat" was made against the school prior to the detonation, though an investigation remains ongoing. 

"Rossiter students are being evacuated and the path for children to evacuate has been cleared," the Lewis & Clark County Sheriff's Office said in a statement. "Parents are asked to pick up their kids at the Little Red Schoolhouse east of the Frontage Road. Sierra Road is closed from Montana to the Frontage Road, and people are asked to avoid this area. Buses are at the Little Red Schoolhouse to keep children warm while they wait for their parents."

Montana Governor Steve Bullock has addressed the incident, saying he was "grateful" that law enforcement officials instituted a fast response. "My office is receiving updates and monitoring this situation as it develops," he said.

A separate report from a regional ABC outlet stated that the device—later described as a "pop bottle secured with duct tape and other components"—was initially found by a school employee on the playground and had already been detonated.

No property damage has been reported. The ensuing investigation is being handled by FBI, the Bureau of Alcohol, Tobacco, Firearms, and Explosives, Montana Highway Patrol, and local police authorities.