A pupil at Pembroke Comprehensive School fired brought a BB gun in Pembroke School today injuring another student.
The Year 11 pupil brought the airgun into school and fired a pellet across the PE changing room.
Pembrokeshire Council said it struck another pupil in the face causing what appeared to be 'superficial injuries'.
Staff at the school called the police and co-operated in tracking down the offender and recovering the weapon.
The injured pupil was taken to hospital for examination.
Dyfed-Powys Police said officers were called to attend to an incident involving a suspected airgun at approximately 12.30pm.
They confirmed the boy responsible is assisting police with their investigation.