By: Brad Evans of WISN12

Police say a police officer shot an armed student at Waukesha South High School.

The shooting happened just before 10 a.m. Monday.

Students were dismissed after they were placed under a lockdown.

School officials told parents the shooting happened after a police officer confronted a 17-year-old boy after receiving information the student was armed with a gun in the school.

Police said the student would not remove his hands from his pants pocket.

They said the suspect removed a gun from his waistband and pointed it at the officer.

The officer ordered the student to drop the gun before the shots were fired, police said.

Witnesses told WISN 12 News they heard at least three shots fired.

Administrators said the confrontation was isolated to one classroom.

Police Chief Russell Jack said multiple officers responded to the classroom.

The school resource officer was present but did not fire the shots.

Some students reported hiding in closets and under desks.

News Chopper 12's Matt Salemme said he saw at least 17 police cruisers at the scene on East Roberta Avenue.

Waukesha police called the response a "critical incident."

"The building is safe and secure," police tweeted. "The suspect is in custody."

Officers said it was an "isolated incident" and they were not seeking any other suspects.

"We are in the investigative stage right now as the scene is stabilized," police tweeted.

Investigators have not said how many shots were fired.

The suspect was taken to a hospital, where he was listed in stable condition.

It's not clear how serious his injuries were.

No officers were injured.

"The safety and security of all students and staff are a top priority," school officials said.

Police said the officer was an 11-year veteran of the department.

According to the Waukesha South High School website, the school resource officer is Josh Tyndall.

The names of the student and officer who fired the shots have not yet been released.

Greenfield police will lead the investigation, with the assistance of the Milwaukee police.

Superintendent Todd Gray called the shooting his "worst nightmare."

The Milwaukee County Medical Examiner's Office said it was not called to the school or hospital.

U.S. Rep. Jim Sensenbrenner commended students, school officials and first responders and said he was monitoring the situation.

No other details were immediately available.