CÉGEP Lionel-Groulx in the North Shore suburb of Sainte-Thérèse went into lockdown as a "precautionary measure" Friday afternoon after a "potential shooter" was seen outside on campus, the school said in a public announcement.

It asked students and staff to confine themselves inside and anyone outside school buildings to "leave immediately."

In a later update, the school said students and staff should stay confined until administrators make an announcement. It also asked locals to avoid the area.

The lockdown ended at around 6:50 p.m. Friday.

Classes are cancelled Monday and the school promised to release additional information about the events of Friday afternoon.

This article's cover image was used for illustrative purposes only.