An Israeli helicopter missile strike on a car in Gaza City killed top Hamas leader Abdel-Aziz al-Rantissi on Saturday, Hamas sources and medics said this evening.
Witnesses said two of Rantissi's bodyguards were also killed in the attack.
Medics said Rantissi had been rushed to a Gaza City hospital in a critical condition after the attack. Sources said he had been wounded in the head with shrapnel.
Hundreds of Hamas members and supporters flooded to the hospital after news of the Israeli raid.
The air strike occurred hours after an Israeli border policeman was killed by a Palestinian suicide bomber at the Erez crossing on the Israeli-Gaza border.
No immediate comment was available from the Israeli army on the helicopter strike.
Rantissi, a co-founder of Hamas, has become one of its two main leaders since Israel's killing of Hamas spiritual head Ahmed Yassin in Gaza on March 22nd.
Israel tried to kill Rantissi, public face of a Palestinian militant group that normally stays in the shadows, 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 since Hamas launched a suicide bombing campaign to spearhead the Palestinian uprising.
He had long depicted himself as a Hamas politician with no links to the military wing. But Israel had 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, camera crews from around the world have trooped to his modestly furnished living room to hear him issue vows of revenge, often in calm, even tones, for Israel's killing of militants.