SALEM, N.H. (AP) – Bullet cartridges were found at Salem High School twice this week and two students were eventually suspended after an investigation.

A teacher discovered the .22-caliber bullet cartridges lying in a hallway Friday, the second incident. School officials said that students were not in lockdown but weren’t dismissed for the next class on time.

“It was just a delay in the start of the second period,” Superintendent Michael Delahanty said.

While students waited, administrators and police went from room to room to determine which students left class during first block.

“Once they finished going from room to room and getting the names of students who had been missing from first block, they had about 50 names,” Delahanty said.

Police narrowed the list down to several people of interest and determined that there was no gun in the school.

The school said more students could be suspended. The students involved could face criminal threatening or disorderly conduct charges.