Nile television said flames from the blast near the town of Al-Arish could be seen up to 20 kms (12 miles) away. It gave no details on the causes of the explosion or the extent of the damages.

But MENA, without citing its sources, said there had been an attack on the station that is used to "export Egyptian gas abroad", including supplying Israel. Egypt also sells gas to Jordan and other countries.

The agency said fire trucks were trying to contain the flames and security forces were hunting down those responsible.

It also said a security guard and his family were injured in the blast.

The explosion was the fourth attack this year on pipelines in Sinai that supply gas to Israel and Jordan.

Egypt's gas transport company, Gasco, a subsidiary of the national gas company EGAS, has been finalising repairs on a pipeline that supplies gas to Israel and Egypt, and was expected to complete the work over the weekend,

A security source had said after the blast on July 4 that men in a small truck who were armed with machineguns forced guards at the station to flee, then planted explosive charges.

Previous attacks on the pipeline on April 27 and on February 5 closed the pipeline for weeks.