Israeli forces assassinated Hamas leader Abdel Aziz Rantissi last night, in what appeared to be the start of a campaign to destroy the organisation before Israel pulls out of Gaza as part of a US-sanctioned deal. That deal, agreed last week, would allow Israel to annexe large areas of the West Bank in exchange.
In a move that immediately attracted widespread condemnation, including from Foreign Secretary Jack Straw who described the killing as illegal, Rantissi was killed with two aides as missiles slammed into his car.
'The British Government has made it repeatedly clear that so-called "targeted assassinations" of this kind are unlawful, unjustified and counter-productive,' Straw said last night.
Rantissi became the head of Hamas following Israel's assassination of Sheikh Ahmed Yassin last month. His death came hours after an Israeli border guard was killed and three others injured in a suicide bombing at the Erez Border Crossing in Gaza. Hamas and the Al Aqsa Martyrs' Brigade claimed they carried out that attack.
Following Rantissi's killing, Hamas immediately vowed revenge and said that it would continue its struggle to destroy Israel.
Ismail Haniya, a senior member of Hamas said: 'Israel will regret this. Revenge is coming. This blood will not be wasted. It is our fate in Hamas, and it is our fate as Palestinians, to die as martyrs. The battle will not weaken our determination or break our will.'
The killing was greeted with anger around the Arab world, where officials and Muslim leaders described the assassination of the new Hamas leader as 'an ugly crime' that indicated Israel's intent to sabotage any peace hopes and accused America of green-lighting it .
For its part, Israel said it had killed a 'mastermind of terrorism' and vowed to keep up strikes on militant leaders. Israel has been braced for revenge attacks from Hamas since it assassinated Yassin last month.
Ahmed Qureia, the Palestinian prime minister, accused the United States of encouraging the assassination. 'The Palestinian cabinet considers this terrorist Israeli campaign is a direct result of American encouragement and the complete bias of the American administration towards the Israeli government,' he said.
The assassination follows Israel's publication of its plan to withdraw from 18 settlements in the Gaza Strip.
Right-wing Israeli critics of the plan say that it rewards terrorism and will encourage more Palestinian violence.
However, Israeli sources say Ariel Sharon is determined that any Israeli withdrawal from Gaza should be carried out in an atmosphere of Israeli military invincibility and that Hamas will be in no position to claim any victory - a determination many believe is behind the killing of Rantissi.
When he took over from Yassin in March, Rantissi, who survived an Israeli assassination attempt last year, insisted that he had no fear of death.
'We will all die one day. Nothing will change. If by Apache or by cardiac arrest, I prefer Apache,' he said.
Rantissi was born in 1947 in the village of Yavna near the southern coastal city of Ashkelon.
During the Arab-Israeli war of 1948 his family fled their home and settled in a refugee camp in the Gaza Strip. He was trained as a doctor in Egypt but returned to practice in Gaza. He was arrested repeatedly by both the Israelis and the Palestinian Authority after it took control of the Gaza Strip in 1994.
Palestinian leader Yasser Arafat praised Rantissi as 'a courageous leader' and said 'the crimes of Israeli occupation' would make the Palestinians more steadfast.
The joint leader of the militant Islamist group Hamas, Abdel-Aziz al-Rantissi, was killed by an Israeli missile attack on his car in Gaza City last night, writes Nikki Knewstub .
Rantissi, 56, was taken to a hospital with but he died soon afterwards. His son Mohammed, 27, and a bodyguard also died, and five pedestrians were wounded.
About 2000 Hamas members and supporters flooded into the hospital after news of the raid. Rantissi has been one of Hamas's two leaders since Israel killed Ahmed Yassin, the group's spiritual leader, on 22 March.
Rantisi's car was hit by missiles in the road outside his home, leaving the vehicle burned out. After the explosion, Israeli helicopters were heard in the area.
He was taken to the hospital critically ill, his body covered in wounds and blood streaming from his head and neck. He was rushed into emergency surgery, but died five minutes after arriving at the hospital.
The attack occurred hours after an Israeli border policeman was killed by a Palestinian suicide bomber at the Erez crossing on the Israeli-Gaza border.
The killing comes at the end of a week of dramatic developments in the Middle East with Israeli leader Ariel Sharon returning from Washington with the unexpectedly wholehearted backing from an electioneering President George W. Bush for his plans to rewrite the road map with even fewer concessions for the Palestinians than before.
Hamas, which has been behind scores of suicide attacks against Israel in the Palestinian uprising and has pledged to destroy the Jewish state, issued an immediate vow of revenge. 'Israel will regret this. Revenge is coming,' said a senior Hamas leader at the hospital.
No immediate comment was available from the Israeli army on the helicopter strike.
Israel tried to kill Rantissi, last June. On that occasion he and his teenage son were wounded in an Israeli helicopter missile strike on his car, also in Gaza City.
Rantissi had refused to go into hiding like many of his comrades on Israel's wanted list He had depicted himself as a Hamas politician with no links to the military wing.
But Israel refused to accept the distinction, accusing him of being a top decision-maker on attacks and of using his media role to incite violence.
With Rantissi filling the role of Hamas spokesman, TV camera crews from around the world have trooped to his modestly furnished living room to hear him issue vows of revenge, for Israel's killing of militants.