Forest View Educational Center in Arlington Heights to reopen on Wednesday, but officer's lost gun still not found

An Arlington Heights school will resume classes on Wednesday, after closing the school for a day to search for a gun that a police officer lost on the school campus. 

According to Arlington Heights police, the officer removed his gun while using the bathroom at the Forest View Educational Center just before classes ended on Monday. 

After class dismissal, the officer realized the weapon was missing. 

A search was conducted by police and K-9 officers from Arlington Heights, Palatine, and the Cook County Sheriff's Office. The gun has not been located. Surveillance cameras are being reviewed. 

"The Arlington Heights Police Department regrets this unfortunate and embarrassing incident," an official said in a written release. 

Township High School District 214 cancelled classes at Forest View on Tuesday as a precaution, and after police confirmed the gun was not in the school, the district said classes would resume on Wednesday, with an increased police presence on campus.

While the gun has not yet been found, police said "detectives have narrowed the scope of our investigation to a small group of individuals connected to this case."

One person of interest has been taken into custody and was cooperating with detectives. Police said they believe the gun was stolen and removed from the school.

"While progress has been made, we want to assure the public we will continue to deploy all available resources to identify those connected to the theft, and recover the firearm," police said in a statement.

The officer who misplaced the gun has been placed on administrative leave pending an internal affairs investigation.

Police are asking members of the school community with information to call detectives at 847-368-5300.