Four people are under arrest in connection with a lockdown at a high school in Halton Region.
Students were stuck inside Georgetown District High School for more than 3 hours on Thursday afternoon.
Police officers swooped in when a staff member reported seeing people at the school who were carrying what appeared to be guns.
Cops searched the building and gave the all-clear after 6:30pm.
Nobody was hurt.
Authorities have so far not released information about the people who were arrested, or provided details on possible charges.