KNOXVILLE, Tenn. (AP) — Multiple people including a police officer were shot Monday at a high school in the east Tennessee city of Knoxville, authorities said, adding that the scene had been secured.

The Knoxville Police Department tweeted that authorities were at the site of the shooting at Austin-East Magnet High School. The online posting said a Knoxville Police Department officer was reported among the victims.

Bob Thomas, the superintendent of Knox County Schools, tweeted later Monday that a shooting had occurred but the building had been secured.

“The school building has been secured and students who were not involved in the incident have been released to their families,” Thomas said. He added in a separate tweet that authorities were gathering information and about “this tragic situation” and that additional information would be provided later.

Police urged people to avoid the area. Details remained sketchy and news outlets showed numerous police and emergency vehicles at the scene.