Six people have been killed by Israeli shellfire during an incursion by Israeli troops into the northern Gaza Strip. Four of the victims were policemen whose security post was destroyed.
The Israeli action was in response to an attack by Palestinian gunmen on a Jewish settlement in the area, in which two young Israelis were killed and 15 people were injured. The two gunmen were shot dead by Israeli troops.
The violence is a serious breach of a ceasefire agreed last month between the two sides. The Palestinian President, Yasser Arafat, condemned the attack on the settlement, but Israel said that it held him and the Palestinian Authority responsible for it.
Israel's Cabinet Secretary, Gideon Saar, claimed the ceasefire had never been respected by the Palestinians, but he did not say specifically that Israel considered the truce to be over.
The latest clashes are also a setback to President Bush's efforts to build an international coalition against terrorism including Arab and Muslim states.
The US Defence Secretary, Donald Rumsfeld, has arrived in Saudi Arabia at the start of a tour of the Middle East and central Asia. But Mr Rumsfeld is expected to face calls to put pressure on Israel to stop attacking Palestinians.
