Al Arish, Egypt : Egyptian security forces launched a search late on Friday for two Sudanese suspected of planning attacks against government installations and tourist resorts in the Sinai, an Egyptian security official said.

The suspects are believed to be driving in an explosives-laden Toyota pickup truck, said the official, speaking on condition of anonymity because he was not authorised to talk to the media.

The search began after urgent instructions from the Egyptian interior ministry to police offices across the Sinai Peninsula.

The official added that the police, including reinforcements sent to the area, have set up ambushes and were searching through main cities in the Sinai and recruited local Bedouin tribesmen to help search for the suspects. Bedouins are traditionally experts at navigating the desert and finding back ways to avoid checkpoints.

"Police forces have beefed up troops in all of Sinai, fearing possible attacks, particularly around big cities, towns and tourist sites," the official said. No other details were available, but residents in the town of Al Arish, some 35km from the Egyptian border with Gaza, and in other remote parts of the Sinai desert, reported seeing scores of policemen setting up check points, stopping and searching cars on main roads and outside government buildings.

The Sinai has been the site of three major bomb attacks since 2004. The blasts in the resorts of Sharm Al Shaikh, Taba and Dahab killed 125 people. The government blamed the attacks on a local militant group, apparently inspired by Al Qaida ideology.

Also on Friday, security forces found an under- ground passage in the Herzallah village on the outskirts of Rafah, a few kilometres south of the border with the Palestinian Hamas-controlled coastal strip.

A group of men reportedly was spotted trying to sneak into Egypt but managed to escape back into Gaza, leaving behind a cache of thousands of US dollars and big boxes of cigarettes, the official said.