May 26, 2015 3:31 PM EDT

Some pests set 72,000 ladybugs loose throughout a Maryland high school as part of a senior prank, the St. Mary’s County Sheriff’s Office said in a news release.

Five suspects wearing masks and hooded sweatshirts broke into Chopticon High School in Morganza, Md., at 3:40 a.m. Wednesday and released ladybugs purchased online in the hallways, while two waited in a car, authorities say.

Four suspects have been charged with burglary, property destruction and disruption of school activities, while the other three have been charged by criminal summons.

Write to Olivia B. Waxman at

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