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Details of threat against CMR High School and arrest of suspect

CMR High School in Great Falls
Henry Douglas Lenning booking photo
CMR High School
Posted at 10:06 AM, Jan 28, 2022
and last updated 2022-01-28 20:58:20-05

GREAT FALLS — Henry Douglas Lenning has been charged after he reportedly threatened a "mass shooting" at CMR High School in Great Falls.

Lenning, 56 years old, was arrested on Thursday, January 27, just hours after the threat was communicated.

Court documents state that the FBI received a tip at about 10:30 a.m. on Thursday that there was going to be a "large scale attack" at the school on Friday, January 28, involving a mass shooting and "several military style firearms and explosives."

The FBI reported the information to the Great Falls Police Department, who coordinated with staff at CMR.

Jesse Rosteck, the Great Falls police officer who serves as the CMR school resource officer, worked with CMR staff to address the threat.

Rosteck explained, “Every threat we receive, we take extremely seriously. They are all handled the same way, we respond to them immediately, and nothing’s put on the back burner. We get on it right away. We really have a good working relationship between the police department and the school administration, so once we get word of a threat, we get everybody together in kind of a team and figure out what the level of threat is and what our response to that threat is going to be.”

CMR released students at the normal time under ‘Release with Care’ conditions, and there was increased police presence at CMR. The ‘Release with Care’ was purely precautionary, the GFPD noted.

GFPD detectives were able to determine the online threat was sent from a computer at the Great Falls Public Library.

During the investigation, a man by the name of Henry Lenning surfaced, as he had reportedly made similar threats in the past using the same method and the same computer IP address.

Henry Douglas Lenning booking photo
Henry Douglas Lenning

Investigators learned that Lenning, who is from Shelby, was currently residing in Great Falls and was a regular at the library.

Police went to the library and found Lenning there; he was questioned and admitted making several threats, including a mass shooting at CMR High School.

There are no indications in the court documents that Lenning had the means to actually carry out the threat.

Lenning is currently jailed in the Cascade County Detention Center awaiting his initial court appearance.

He has been charged, at this point, with felony intimidation. If convicted, Lenning could face up to 10 years in prison and/or a fine of up to $50,000.