More than 60 New Jersey high school seniors were arrested early Thursday after they allegedly broke into their school for a class prank overnight, urinating in the hallways, flipping desks and greasing door handles, police say.

Police responded to a burglary alarm at Teaneck High School shortly before 2:30 a.m. When they arrived, several students tried to run away but officers found dozens of teens still there, some hiding, and significant damage throughout the school, according to Teaneck Police Sgt. John Garland.

Garland said officers found balloons throughout the building, flipped desks, petroleum jelly on doorknobs and urine in the hallways. Police also watched some of the alleged criminal activity on the closed-circuit security system as it was happening.

"I've been a police officer 19 years, and this is the craziest thing I've ever seen," Garland said.

Several of the students allegedly told police that it was all part of a senior class prank, he said.

"They're learning the hard way that it's not too funny," Garland said.

About 10 law enforcement agencies responded to the scene. Officers had to make several trips to transport the students to the precinct, because there were so many kids taken into custody.

Sixty-two students were arrested. Thirty-eight of them are juveniles and were released to their parents, police said. The other 24 are 18. All face burglary and criminal mischief charges.

"They're all in some pretty serious trouble," Garland said.

Teaneck High School principal Dennis Heck told NBC 4 New York that school was open Thursday.

"You can imagine how disappointed I am," he said.

Superintendent Barbara Pinsak said the school district was weighing its options for disciplinary action.

Thursday morning, balloons and streamers could still be seen strewn about the floor of the school.