HARRISON TWP. — The sweet sting of waiting for winter break was drawn out a little longer for students at the Clearview Regional school district on Tuesday.

The middle and high schools were put on lockdown over the course of about 90 minutes for what officials called "precautionary measures" after a custodian found .22 caliber ammunition in the parking lot.

Lt. Ronald Cundey of the Harrison Police Department said a maintenance staff member had found a single round near the media center entrance to the building.

"It was laying on the ground, and we don't even know how long it was there," Cundey said. "It could've even been from last night."

Police from several jurisdictions with K-9 units searched the school on Breakneck Road, as indicated in an announcement the district posted on its website a little after 11 a.m.

"We are currently in a lockdown for precautionary measures. We are working with Mantua and Harrison Township police departments to do a quick investigation to resolve the situation," said the school's release.

Cundey said that "at no time were any students or staff in danger." No weapons were discovered, and there were no reports of threats.

A secretary at Clearview said all students and staff were safe, and that the main concern Tuesday was getting students on buses for the district's early dismissal before winter break. Students were supposed to get out at 12:15 p.m.

The sweep was completed by 1 p.m.

Andy Polhamus may be reached at apolhamus@southjerseymedia.com. Follow him on Twitter @ajpolhamus. Find the South Jersey Times on Facebook.