Kyle Curtis

An automated call from Del Norte County Unified School District at 10:50 a.m. informed parents that each school is on high alert while a bomb threat made on a web-based application last night "to an unknown school" is investigated.

The call said that the threat was considered likely to be a prank, but schools Superintendent Don Olson authorized the alert as a precaution.

Police, sheriff and the District Attorney's Office are visible at schools today as they work to identify the student who made the threat, the call said.