Firefighters from Tenby were called to a blaze at a derelict school yesterday (Wednesday) evening.
Crews arrived at the site of the former Netherwood School, near Saundersfoot, at 5.15pm. They found an outbuilding classroom well-alight.
Firefighters were at the scene for just over half an hour and used two sets of breathing apparatus and two hose reel jets to extinguish the fire.
Police are investigating the blaze and are asking anybody with any information to contact Tenby police station on 101.
Netherwood School, a privately owned boarding school, closed in 2009.