A ten-ton load of explosives packed into a water tanker detonated, killing the bomber and a civilian motorist, police in ths city of al-Arish said on Tuesday. Flying debris injured about 35 policemen.

Egypt's interior ministry said it was aware that the water tanker truck had gone missing and had been searching for it when the al-Arish bombing occurred.

Security forces had "repelled" the intended attack by firing at the truck as it approached, the ministry said.

In a second assault near a checkpoint in southern Arish, a roadside bomb exploded, killing one army officer and wounding three others, security sources said.

An investment conference, the Sharm el-Sheikh summit, backed by Egypt's sponsor, the United Arab Emirates, is due to open on Friday in Sharm el-Sheikh, which lies some 320 kilometers (210 miles) south of al-Arish, the scene of Tuesday's bombings.

Sinai scene of various attacks

Though there was no immediate claim of responsibility, Islamist militants based in Sinai have killed hundreds of soldiers and police since 2013 when Egypt's army toppled Islamist president Muhammed Morsi.

The region's largest jihadi force, which calls itself the Sinai Province of Islamic State, claimed responsibility for a coordinated attack in January on al-Arish that killed at least 40 members of Egypt's security forces.

Last year, the Sinai-based militants claimed allegiance to self-styled "Islamist State" extremists who seized swaths of territory in Syria and Iraq last year.

UAE major sponsor of Egypt

The oil-rich Emirates has become a heavy sponsor of Egypt since its economy was gutted by turmoil in 2011 and is a key organizer of the Sharm el-Sheikh economic conference.

Guests invited include executives from US-based blue-chip concerns and from aviation, banking and energy sectors in the Emirates' seven state federation.

The UAE is home to about 9 million people compared to Egypt's 90-million population.

The Gulf federation is also involved in the US-led coalition that flies air strikes against "Islamic State" insurgents in parts of Syria and Iraq.

ipj/sb (dpa, AP, Reuters)