A general view of the Chevron Oil Refine [Getty Images]

A general view of the Chevron Oil Refinery near Pembroke in west Wales is pictured on June 3, 2011. An explosion at one of the largest oil refineries in western Europe killed four contractors and sent a massive fireball shooting into the sky, British police said on Friday. The blast at the Chevron refinery near Pembroke, on the coast of southwest Wales, could be heard across the area and sent fire crews scrambling to the scene. AFP PHOTO/Paul Ellis (Photo credit should read PAUL ELLIS/AFP/Getty Images)

AFP PAUL ELLIS