Joliet Central High School briefly activated a “teach and hold protocol” on Thursday to secure the building while Joliet police pursued a suspect in the area.

A notification was posted on the Joliet Township High School District 204 website and Facebook page on Thursday morning, stating that the school was operating under lockdown protocol to secure the building, but that students and staff were safe.

The notification also warned parents and family members to stay away from the school.

“Do not report to school at this time because this will cause a disruption to the safety protocol procedures and you will not be able to enter the building or pick up any student,” the announcement said.

All of the building’s exterior doors were secured, and no one was allowed to enter or exit the building. The notice was activated around 10:30 and was lifted around 11:15 a.m.

The district informed the Herald-News that the lockdown was initiated “due to an incident in close proximity of the school with the Joliet Police Department pursuing a suspect near Central.”

Joliet Police Public Affairs Sgt. Dwayne English said the incident involved a suspect who fled from police during a traffic stop.

“This morning at 10:19 a.m., officers attempted to conduct a traffic stop on a vehicle near North Eastern Avenue approaching Cass Street,” English said. “The vehicle refused to stop and sped away from the officers, who did not pursue.”

The vehicle was then involved in a crash at the intersection of North Eastern Avenue and Cass Street, and its two passengers exited and ran, English said.

The driver was taken into custody, and a firearm was recovered inside the vehicle, he said.

“As a precaution, Joliet Central was requested to activate their secure building, teach and hold protocol, for a short period of time as this investigation progressed,” English said, noting that the investigation had nothing to do with the school and is still ongoing.

During a “hold and teach” protocol, students are kept in their classrooms and class continues as planned. However, passing periods and class changes are not observed to keep the halls clear until the lockdown is lifted.

With the protocol officially ended, students and staff were allowed to resume their normal daily schedules.

The lockdown at Joliet Central sparked concerns on social media, especially as it comes one day after a shooting at Evergreen High School in Jefferson County, Colorado, which the Denver Post reports left two students hospitalized and the shooter dead. As of Thursday morning, one student remained in critical condition.

The Evergreen High School shooting happened within an hour of another violent incident, in which far-right activist and podcaster Charlie Kirk was killed in a targeted shooting during his speaking event on the campus of Utah Valley University in Orem, Utah. No other injuries were reported on the Utah campus.

District 204 thanked parents and the community for their cooperation during the lockdown, stating repeatedly throughout the morning that “the safety and security of our students and staff is always our highest priority.”