Some senior pranks are harmless, stupid fun. Others will get you arrested on felony charges of “perpetrating a hoax by use of false bomb or other device in a public building.”

Yesterday morning, as part of their senior prank, Shannon Marie Farrell,18, and Lekia Hall,18, reportedly set several alarm clocks to different times and then locked them in unused lockers at South Iredell High School in Statesville, North Carolina.

After hearing ticking sounds and noticing that the locker’s zip-ties had been replaced with actual locks, a school administrator called 911. Law enforcement officers—including officers from Iredell County Sheriff’s Office, the N.C. Highway Patrol, and local EMS and fire stations —quickly swarmed the building and evacuated its more than 1,500 students and 200 employees to the football field.

The perpetrators, who apparently had sent out emails about the pranks several days prior, were quickly identified and questioned. From the Statesville Record & Landmark:

Dan Farrell, speaking near the school, said he received a call from his younger daughter Tuesday morning. He said she told him her sister was being questioned and the school had been evacuated.

He said he heard about the plans to bring alarm clocks to school several days ago. “I thought it was a pretty funny thing,” Farrell said.

Troutman Police Chief Matthew Selves, however, did not think the prank was a pretty funny thing. From the Record & Landmark:

Selves said a lot of resources were tied up for about two hours until a bomb-sniffing dog made a sweep through the school and word of the planned prank began to make its way to investigators.

He said the whole situation could have been avoided if any of those who knew of the planned prank had alerted an official ahead of time.

If convicted, Farrell and Hall could be sentenced to four to 25 months in prison. The prank is the second this week that’s ended with the arrest of students. At least America’s teens are focusing on something, for once.

Image via Shutterstock. Contact the author at taylor@gawker.com.