Tens of thousands of Palestinians took part Sunday in the funeral for the Hamas leader in the Gaza Strip, Abdel Aziz Rantisi, killed Saturday in an Israeli air strike. His death is another formidable blow to Hamas, whose founder and spiritual head was assassinated only three-weeks ago by Israel.

Even after his death, recordings of fiery Rantisi speeches urged Hamas followers to continue their violent attacks on Israel.

Mr. Rantisi was a long-time spokesman for the organization before becoming Gaza leader last month following Israel's assassination of the Hamas spiritual leader, Sheikh Ahmed Yassin.

He warned then that the sheikh's death would only inspire Hamas to step up its campaign of violence. "The road is opened. I know that they [Hamas members] will succeed in assassinating the political leaders [in Israel]," he said.

But Israel acted swiftly to stop Mr. Rantisi from carrying out his dire threats.

An Israeli helicopter fired missiles at his car late Saturday in Gaza City. Although he was pulled alive from the burning wreckage, he died later on the operating table. Two bodyguards in the car were also killed. Israel held Mr. Rantisi directly responsible for the deaths of Israeli citizens. Foreign Affairs Ministry spokesman Jonathan Peled says he was targeted to prevent more innocent people from being killed.

"Israel is compelled to continue fighting against terrorism and struck a mastermind of terrorism, a man with blood on his hands, the head of the Hamas terrorist organization, that is responsible for the deaths of hundreds of Israelis," he said.

In fact, Mr. Rantisi had been a marked man long before he took over the leadership in Gaza. He survived an earlier assassination attempt in June last year.

Mr. Rantisi rose to prominence after becoming one of the founders of Hamas in 1988.

He was born in 1947 in a village near the coastal city of Ashkelon. It became part of Israel one year later when the Jewish state was created. The Rantisi family became refugees and moved to a camp in the southern Gaza Strip.

As a young man he studied medicine in Egypt and returned to work in Gaza as a pediatrician. But politics became his real passion. He was arrested for the first time in 1983 for attempting to organize a tax revolt against the Israeli administration in Gaza.

He was jailed again in 1990 and two-years later was one of 400 Palestinians exiled to Lebanon by Israel, but the group was allowed to return home following a storm of international protest.

He immediately re-dedicated himself to Hamas, which has sworn to destroy Israel and establish an Islamic state.

He soon got in trouble with the newly formed Palestinian Authority. In 1998, he was jailed after demanding some members of the authority resign. He publicly opposed efforts by the, then, Palestinian Prime Minister Mahmoud Abbas to revive peace talks last year with Israel.

A new man has been selected to take over Hamas in Gaza, but he will not have the high Rantisi public profile. The organization says he will remain nameless and hidden from view.

In the last few weeks of his life, Mr. Rantisi said he wanted to die a martyr for the Palestinian cause. Israel granted him his wish. Hamas says it does not want his successor to share the same fate.