UPDATE: A-C Valley School District will be on a two-hour delay Tuesday morning.

FOXBURG, Clarion Co. — The Allegheny-Clarion Valley School District was placed on lockdown late Monday afternoon.

Superintendent David McDeavitt said at just after 5 p.m. that a threat was received after student dismissal and the lockdown affected those remaining on campus.

He said students were dismissed and left school on their buses before the lockdown was initiated.

McDeavitt said he contacted Clarion State Police and canceled all evening sports and activities in the district.

He did not know how many people were affected by the lockdown or how the threat came in.

State police in Clarion are investigating but could offer no further information on the situation.

This is a breaking news article — check for updates to this article in Tuesday's Butler Eagle.