Authorities were called to Waukesha South High School about 10:15 a.m. Monday, Assistant Fire Chief Joseph Hoffman says.
Waukesha police and sheriff's deputies soon arrived at the school and tried to de-escalate the situation to no avail.
The Milwaukee Journal Sentinel reports shots were exchanged between a student and a school resource officer. "The suspect removed his handgun from his waistband and pointed it at the officers".
Waukesha North High School's lockdown happened before 2 p.m. Monday afternoon. "An officer was forced to discharge his firearm, striking the suspect". They didn't immediately respond to a phone message seeking additional detail.
No officers or other students were injured, Jack said. He is in stable condition. The Waukesha mayor's office said that one suspect is in police custody, and it is believed to be an "isolated incident". Jack says the officer who shot the student is an 11-year veteran of the Waukesha police department.
Waukesha Mayor Shawn Reilly said that it was a "terrifying day for many students and parents".
Terry Schuster, a spokeswoman for the school district, confirmed the incident to The New York Times, telling the newspaper the student "did not comply to hand over the gun".