A Scarborough high school was locked down for about 90 minutes Monday after a gun was found in a locker.
Police said they were called to Albert Campbell Collegiate Institute at 1550 Sandhurst Circle shortly before 10 a.m. after the weapon was located during a locker check.
The lockdown was lifted at 11:23 a.m.
"We're still trying to find out who's responsible," Const. Tony Vella said.
No one was hurt.
Albert Campbell is one of 28 Toronto schools that has been assigned a school resource officer.
Anyone with information is asked to call 42 Division at 416-808-4200 or Crime Stoppers at 416-222-TIPS (8477).