One appliance and crew from Maidenhead and one from Windsor Tinkers Lane attended, along with three officers.
The firefighters used two sets of breathing apparatus, two hose reels, a thermal imaging camera, and an environmental pack.
A road closure was put in place, and the firefighters remained on the scene to assist Thames Valley Police.
Sadly three men died at the scene.
The incident investigation has been handed over to Thames Valley Police, and an appeal for witnesses has been issued.