A 49-year-old security officer at Ponderosa High in Douglas County has been arrested on suspicion of sexually assaulting a student at the school.

According to the Douglas County Sheriff’s Office, Gary Postell was taken into custody after deputies received a report late Monday afternoon that a sexual assault had occurred at the school, located at 7007 Bayou Gulch Road in Parker.

Postell was being held on a $5,000 bond pending a decision about the filing of formal charges. He is tentatively scheduled to appear in court Friday morning.

A spokeswoman for the Douglas County School District told 9NEWS that Postell has been with DCSD since September 2014.

“This allegation is certainly concerning and we take any reports of this nature seriously," DCSD spokeswoman Paula Hans said in a media statement. "Douglas County School District does not tolerate inappropriate staff conduct towards our students. Due to privacy laws and the law enforcement investigation surrounding this allegation, we are unable to discuss this matter specifically.

"However, if we receive allegations of this nature, we immediately contact law enforcement, begin our own investigation and possibly place the staff member on administrative leave during the investigation. We do not condone any inappropriate staff conduct, and we cooperate fully with our law enforcement partners.”

According to Colorado Bureau of Investigation records, Postell was jailed on suspicion of three counts of sexual assault on a child.

The alleged assault, which occurred at the school, was reported about 5:30 p.m. Monday, according to the sheriff’s office.

Douglas County sheriff’s investigators interviewed the student, they concluded there was enough evidence to arrest Postell.

He was being held at the Douglas County Detention Center, but was later released after posting bond.

He's currently on unpaid leave.

Contact 9NEWS reporter Kevin Vaughan with tips about this or any story: kevin.vaughan@9news.com or 303-871-1862.