PLACER COUNTY (CBS13) – A lockdown that was put in place at Granite Bay High School has been lifted.

The Placer County Sheriff’s Office confirms that the school went on lockdown a little after 2 p.m. after a threatening note was found on campus. The lockdown was later lifted and sheriff’s deputies went room to room searching for any sign of a potential threat. As of now, no threat has been detected.

Buses were postponed while deputies investigated, but parents were told they could pick up their kids as usual.

Classrooms were released one by one, school officials say.