An investigation revealed that four Cleveland High School students were involved in a firecracker incident inside the school Monday morning.

At about 7 a.m. Monday, the school’s gunshot detection system was activated after a firecracker went off inside of a hallway. Rio Rancho Public Schools Safety and Security immediately responded and found no evidence of any “gun incidents or shots.” Instead, they found a used firecracker, RRPS spokeswoman Melissa Perez told the Observer.

No one was hurt and classes proceeded as usual.

The students will face disciplinary action that may include suspensions, she said.

To protect student privacy, RRPS is unable to provide additional details about the students, Perez said.