NORFOLK, Va. (AP) — A student lit one or more bullets he was holding in his hand in a Virginia high school classroom, causing a minor explosion and requiring treatment for his injuries, a school system spokeswoman said.

Norfolk Public Schools spokeswoman Barbara M. Hunter told news outlets that the incident occurred in a science class at Maury High School on Friday afternoon. Hunter said the unidentified student was treated by a nurse before he was taken to a local hospital.

No other injuries were reported.

The high school was placed on a lockdown that was lifted around 2:45 p.m. Hunter said officials expected some delays in buses getting students home.