A lockdown has been lifted at a Cape Breton High School after police responded to a weapons complaint.

Cape Breton Regional Police were called to Riverview High School in Coxheath, N.S. after 10 a.m. after a note was found, claiming there may be a weapon inside.

At least eight police cars, 20 officers and a K9 unit attended the scene.

The school was on lockdown and access was restricted for more than four hours while officers searched the building.

"They were asking us to stand in line. They did the pat down that you would see at an airport," said Grade 12 student Brendan Crummey. "They had metal detectors, same as you would have in an airport, and one guy was going around with gloves on, searching each bag."

A group of parents waited outside the building as police scoured the area.

"I felt helpless, pretty helpless, knowing that my daughter was in there and we couldn't do anything out here to help," said parent Wendy Aboud.

Police have now completed their search of the school. They said there was no evidence of a weapon or threat to students’ safety.

The students were dismissed around 3 p.m.

According to the school’s website, Riverview High is one of the largest high schools in Cape Breton. Roughly 900 students attend the school, which offers grades 10 to 12.