HUNTINGTON BEACH, Calif. – Huntington Beach Police locked down the local high school Tuesday morning for over three hours to search for a former teacher who was spotted on campus.

Police officer Jennifer Marlatt told the Huntington Beach Independent officers were called to Huntington Beach High School around 8:30 a.m. because a teacher spotted a colleague who was fired last year walking away from the building.

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Media reports did not detail why the situation caused alarm, but police opted to issue a “shelter in place” order that locked students and staff in classrooms while they repeatedly searched for the unnamed former teacher. Around noon police gave up without finding him and lifted the order, The Orange County Register reports.

The former teacher is apparently banned from campus unless he first meets with the front office, which he did not do. School and police officials would not discuss why the teacher was fired. The man did not appear to have any weapons and nor did he make any threats, police said.

“The administration staff ensured we had people in place to assist with students who asked for assistance during this time,” Principal Daniel Morris wrote in a statement to parents, according to the Independent. “The Police Department and district office worked together to ensure all possibilities were thoroughly checked and followed up on.”

Several locals discussed the issue on Twitter and alerted the media.

“X Physics teacher causes lock down at Huntington Beach High School and parents aren’t notified by emergency alert @CBSNews @Huffington Post,” Marcia White tweeted.

“Not true I received the call at 10:10 am just seconds after my daughter texted me,” Karlie Savage responded.

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“Just talked too (sic) my doctor she wasn’t notified she has two daughters there … maybe a mix up?” Marielle added.

Others commented on the CBS Los Angeles website.

“Have to wonder what the teacher did to get fired – because no teachers ever get fired,” Trusty posted. “Well, okay, about 6 a year in California out of a half million teachers.”

“He was probably teaching honesty and personal accountability,” ImaNiglet responded. “Two things liberal school administrators can’t tolerate or replicate.”