By Sadie Gurman and Donna Bryson, Associated Press

DENVER (AP) — A suburban Denver school district is arming its security staff with military-style semiautomatic rifles in case of a school shooting or other violent attack, a move that appears unprecedented even as more schools arm employees in response to mass violence elsewhere.

The Douglas County School District guards are former law enforcement officers and already carry handguns.

District security director Richard Payne said he decided to spend more than $12,000 on the Bushmaster brand rifles for the district's eight armed officers to give them the same tools as law enforcement, including the sheriff's deputies they train with. Payne said the rifles will be kept locked in patrol cars, not in the schools.

Payne said he made the decision to buy assault rifles himself and the school board has not discussed it. The superintendent approved the purchase after lengthy discussion, district spokeswoman Paula Hans said.

"Overall, parents recognize that based on lessons learned, we must be prepared," she said.

The move raised new questions about how far school officials should go in arming employees, a practice that has become standard in the aftermath of the 2012 Sandy Hook Elementary School shootings.

Districts across the nation rushed to increase the number of school resource officers on campus and, in a few cases, allowed teachers to carry concealed weapons themselves.

In Colorado, where the scars of the 1999 Columbine High School massacre still run deep, volunteer reserve sheriff's deputies patrol some elementary schools, and an armed resource officer was credited with stopping further violence at a suburban Denver high school in 2013 by cornering a student gunman, who then shot himself.

Ken Trump, a school safety consultant in Cleveland, said the Douglas County case may mark the first time a district has equipped its in-house security officers with semiautomatic rifles.

"Taking this step certainly ratchets up a notch the whole idea, the question of what's reasonable, what's necessary in terms of arming officers," Trump said.

The Bushmaster rifle is a semi-automatic descendant of the original M-16 automatic rifle used by the military in Vietnam.

Versions of it are made by different manufacturers, but a Bushmaster rifle was used in the Sandy Hook shootings. Victims' families are suing the company, claiming it is a military weapon that should not have been sold to civilians.

A gunman used a similar weapon in a 2012 attack on a suburban Denver movie theater in which 12 people were killed and 70 injured.

Mass shootings underscore the need for school officers to have access to rifles so they're not outgunned, said Mo Canady, executive director of the National Association of School Resource Officers.

"We're not talking about officers walking around with this strapped on all day long, but certainly to have reasonable access to defend against a really bad situation," he said.

Securing the weapons will also be a challenge, Trump said, adding that it was not clear officers would have time to get their weapons when they needed them.

Douglas County's plan could work if the security staff has the right credentials and training, Canady said.

The eight security officers who will be equipped with the new weapons receive the same training as their active duty colleagues, Hans said.

They will have to complete a 20-hour training course before the rifles are distributed. The first few guns will be deployed by next month and the rest will be handed out in August, Payne said.

Colorado state law empowers school districts to arm their security guards. Other Denver-area school districts provide their security guards only with handguns; some have no firearms at all. Police officers who work as school resource officers carry police-issued weapons.

Associated Press writers Colleen Slevin and P. Solomon Banda contributed to this report.

To Learn More:

20 Teachers and Staff Will Carry Guns When Doors Open to Kids at Arkansas School This Fall (by Danny Biederman and Noel Brinkerhoff, AllGov)

Insurance Company Refuses to Insure Schools with Armed Employees (by Matt Bewig, AllGov)

Fontana School Police Buy Assault Weapons, but Don’t Tell District Board (by Ken Broder, AllGov California)