RAFAH, Dec 12: At least four Israelis were killed on Sunday when Palestinian militants detonated explosives packed in a tunnel by an army post on the border between the Gaza Strip and Egypt, officials said.

A spokesman for Israeli Prime Minister Ariel Sharon confirmed that at least four people had been killed in the blast, while military sources said that more than a dozen others had been wounded.

The explosion, claimed by the Palestinian radical Islamic movement Hamas and an armed offshoot of the mainstream Fatah faction, triggered a fierce bout of fighting which left at least one Palestinian civilian dead.

The Fatah Hawks organisation said that one of its fighters, named Mohayed Al Agha, was killed in the operation. The incident came just hours after eight Palestinian pupils and their teacher were wounded by Israeli fire in the nearby town of Khan Yunis, and it further dented hopes that a cease fire could be on the horizon.

The armed wing of Hamas and the Fatah Hawks said in a joint statement that their fighters had packed 1.5 tonnes of explosives into the tunnel during a "suicide mission". They also pledged to continue carrying out such attacks "until we have kicked the occupiers out of our land."

Israel is due to pull all its troops out of the Gaza Strip by the end next year, although a small number are expected to continue manning the volatile Rafah crossing as part of Sharon's controversial disengagement plan.

Mr Sharon's spokesman Raanan Gissin said the attack would not derail the planned pullout but could prevent it being coordinated with the Palestinians. "This attack will not prevent Israel from implementing its disengagement plan but this disengagement cannot be coordinated with the Palestinian Authority unless they act against the terrorist organisations," Gissin told AFP.

Mr Sharon had been indicating in recent days that he was prepared to involve the Palestinians in the pullout, with the emergence of a more moderate leadership in the wake of veteran leader Yasser Arafat's death last month.

The attack at the Rafah crossing came just five days after an Israeli soldier was killed in a bomb attack at the Karni border crossing between Israel and southern Gaza.

The Erez border crossing between Israel and northern Gaza has also been the scene of a number of Palestinian attacks. Army spokesman Captain Jacob Dallal said the latest attack seemed to follow a pattern. "It was a very serious, well-coordinated attack at a major artery," he told AFP.

"We are seeing a concentration by the terror groups to attack the few very, sensitive crossings in and out of Gaza." Welcomed by western countries as a step towards peace, the Gaza plan took a major step at the weekend as the centre-left opposition Labour Party started talks with Mr Sharon's right-wing Likud on a government to champion withdrawal. -AFP