Police say four students have been arrested after a loaded handgun was located inside an east-end school Wednesday afternoon.

Officers found the gun in a knapsack inside Blessed Mother Teresa Catholic Secondary School near Neilson Road and Mclevin Avenue after receiving a tip at around 1:40 p.m.

One girl and three boys between the ages of 16 and 17 were arrested at the scene.

The students were passing the knapsack back and forth to avoid being caught, police say.

It is not immediately known which suspect brought the gun to school.

The school was initially placed under a hold and secure order as officers searched the property; however that order was lifted at around 3 p.m.

Classes were then dismissed at the regular time.

“Our first priority was the safety of the students and obviously nobody has been hurt. Now the second priority is to find out why that gun was brought to the school,” Const. Tony Vella told CP24 Wednesday afternoon. “That’s something officers will be following up on.”

According to Toronto District Catholic School Board spokesperson John Yan, students at the school were “calm” and followed instructions as news of the incident spread, allowing for a quick resolution. 

Yan added that the school will review security procedures in the wake of the incident.

“We will be following up to ensure that our security measures are as up to date and current as possible,” he told CP24.

A voicemail explaining the incident has also been left with parents of students at the school.

Classes are expected to resume as scheduled on Thursday.

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