Updated

Security officials say gunmen have attacked Egypt's gas pipeline to Israel in the northern Sinai Peninsula.

It is the sixth attack on the pipeline since the popular uprising that ousted longtime Egyptian leader Hosni Mubarak in February.

The officials say assailants in two pickup trucks struck a pumping station on the pipeline about 15 miles west of the region's main city of el-Arish before dawn Tuesday, causing a loud explosion and fire.

It was not immediately clear whether the blast was the result of gunfire or whether the gunmen planted explosives and detonated them.

The officials, who spoke on condition of anonymity because they are not authorized to brief the media, said one person was injured in the attack.