Abdel Aziz Rantisi (search), the Hamas leader assassinated in an Israeli air strike Saturday, was one of the highest profile and most extreme voices of the violent Islamic group.

He served as Hamas leader in Gaza for less than a month after Israel killed his predecessor, Hamas founder Sheik Ahmed Yassin (search), in a similar helicopter missile strike on March 22.

Rantisi rejected any accommodation with Israel, following strict Hamas ideology that called for destruction of the Jewish state in the Middle East.

A pediatrician by profession with a reasonable command of English, Rantisi was readily available to foreign journalists and was one of the most recognizable of Hamas' leaders.

Even before he was chosen to replace Yassin, Rantisi was in Israeli gunsights. Last year, an Israeli helicopter fired missiles at his vehicle, wounding him.

Rantisi, 56, was undeterred by the Israeli attempts to kill him and seemed to predict his death.

"It's death whether by killing or by cancer; it's the same thing," he said the day after he was chosen Hamas leader in Gaza. "Nothing will change if it's an Apache (helicopter) or cardiac arrest. But I prefer to be killed by Apache."

Rantisi also told journalists that day, "My priority is to unite the Palestinians in the trenches of resistance because there is no one left who believes in something called the peace process."

Rantisi, Yassin and five other men founded Hamas (search) in 1987 at the start of a first uprising against Israel's occupation of the West Bank and Gaza Strip. The group grew into one of the region's largest militant Islamic factions and called for a Muslim Middle East without a Jewish state.

In the early 1990s, at the start of Israeli-Palestinian peace talks that Hamas opposed, the group pioneered suicide bombings in Israel. During the current conflict, which has lasted more than three years, the group has killed hundreds of Israelis in suicide bombings and shooting attacks.

Rantisi was born on Oct. 23, 1947, in Yibnah, now the Israeli town of Yavneh. He was the fourth of 12 children. When he was 6 months old, his family fled the war that came with Israel's creation in 1948.

The family ended up in the Khan Younis (search) refugee camp in southern Gaza. Rantisi moved to Gaza City during the first uprising.

After co-founding Hamas, Rantisi was the group's first leader to be captured and imprisoned by Israeli forces. Altogether, he spent seven years in prison.

During one confinement, he shared a cell with Yassin and committed to memory the Quran, the Muslim holy book of around 600 pages — an achievement he spoke of proudly.

In prison, he also once meticulously assembled a model of Jerusalem's Al Aqsa Mosque from empty cartons of milk, cigarettes and toothbrushes. He displayed the colorfully painted memento of his prison days on a table in his living room.

In 1992, after the killing of a soldier, Israel sent Rantisi and more than 400 other Islamic militants into temporary exile in southern Lebanon. There, Rantisi first became internationally known, using his command of English to become a spokesman for those deported.

Back in Gaza a year later, Rantisi, with a gray-flecked beard and gold-framed glasses, quickly became one of the group's most recognizable faces, serving as a Hamas spokesman, welcoming journalists to his apartment in Gaza City's Sheik Radwan neighborhood.

Rantisi was targeted by Israel's air force in June of last year. He leaped from his jeep as a helicopter missile pounded the vehicle. Six other missiles pulverized the jeep with thunderous bangs, killing Rantisi's bodyguard and a bystander and wounding his son Ahmed.

As he ran, Rantisi was hit in the leg by machine gun fire from the chopper.

Fellow Hamas founder and surgeon Mahmoud Zahar operated on Rantisi to repair damage to arteries in one of his legs. Recovering at Gaza's Shifa Hospital, Rantisi vowed Hamas would crush Israel: "I swear we will not leave one Jew in Palestine."