By ANDY GARDNER

POTSDAM -- Several police agencies at Potsdam High School on Wednesday may have appeared to be respondong to a serious situation to passers-by, but it was just a drill.

Law enforcement was practicing at the school how they would respond if someone showed up and started shooting.

"Active shooters at school, as many people are aware, is a big concern for any police agency, so the best way to prepare for one of those is to train for it," Potsdam Police Chief Kevin Bates said. "It was a drill for the school as well."

He said his officers, along with SUNY Potsdam University Police, U.S. Border Patrol and a couple of Massena Police officers, who were there to observe. Potsdam Volunteer Rescue Squad and Fire Department also took part, which included treating simulated casualties, according to Potsdam High School principal Joann Chambers

She said the students and staff also had a role to play. They are instructed to stay in their rooms with the doors locked and no students are allowed in the halls. She said it happens during a class period, so teachers are still able to give instruction at the same time.

"It was like nobody was in the school," Chambers said. "We're becoming very accustomed to what we're supposed to do in a lockdown situation."

Bates said the drill went well, by and large.

"We were very pleased with how it went," he said. "There were some minor mistakes we made and we talked about them, which makes us that much more prepared."