Fourteen firefighters from Pembroke Dock, Milford Haven and Haverfordwest fire stations tackled a vehicle fire in Freshwater West shortly after 6 pm on Friday.
The blaze, involving a commercial 22-seater coach, was extinguished using hose reel jets, breathing apparatus and a thermal imaging camera.
All passengers and the driver were safely accounted for.
Firefighters used National Resources Wales environment protection equipment to contain the small amount of oil spilled on the road from the incident.
Firefighters left the scene at 8.29 pm.