Malmstrom Air Force Base in Cascade County, Montana.
CNN  — 

A Montana Air Force base went on lockdown for 10 minutes Thursday morning after “a suspicious person was reported on base as an active shooter,” the base said in a Facebook post.

“There were no confirmed shots fired and there are no casualties or injuries reported,” the post said. “There is no threat to the public at this time. The investigation into the incident is still ongoing.”

A spokesperson for Malmstrom Air Force Base in Cascade County told CNN that the real-life active shooter situation followed an active shooter drill Thursday morning.

The Air Force base initially announced the lockdown status at Malmstrom Air Force Base in Cascade County at 10:29 a.m. local time. The base advised people to “shelter in place.” The lockdown was lifted as of 10:39 a.m., according to the base.

According to a Great Falls Police Department social media post, police were “actively working the situation by providing security and support in the area of the base and nearby schools” during the lockdown.

“We appreciate the community’s patience as we support Malmstrom Air Force Base personnel,” the post said.

This story has been updated with additional information.

Correction: A previous version of this story had the wrong location for the Air Force base. It’s in Cascade County.