The former student who threatened a South Whidbey School District staff member is in police custody, a school official said.

The student, whose name and age were withheld, was last enrolled in November 2011.

“We had a former student who made a threat,” said District Superintendent Jo Moccia. “He has been found and is in custody.”

Last week, school officials were notified of a threat made on the social networking website Facebook. Moccia had schools use a perimeter lockout, which closed and locked all doors except the front doors closest to the main office, and visitors were required to sign in and wear a name tag.

“It was a reiteration of a threat made back in the fall, and it was done on Facebook,” Moccia said.

The Island County Sheriff’s Office and Langley Police Department were notified. Both law enforcement agencies searched for the former student and provided security at the campuses for part of the day Thursday.

All of the district’s facilities – Langley Middle School, South Whidbey Elementary School, the South Whidbey Primary Campus, South Whidbey High School and Bayview School – were again on lockout procedures Friday.

The lockout was suspended Monday and classes were back to normal.