The stunning victory for Hamas in the Palestinian parliamentary elections has catapulted the organisation's leadership, until recently a closely-kept secret, into a pivotal role in international politics.

The Islamist group was decapitated by two Israeli airstrikes in the spring of 2004, when its leader, Ahmed Yassin, and his successor, Abdel Aziz Rantisi, were assassinated within a month of each other.

Since then, a handful of lower-profile leaders have emerged to add a pragmatic side to the party that has launched at least 60 suicide bomb attacks and still officially calls for the destruction of Israel.

Khaled Mashal, a physics teacher in his late forties, is the supreme leader of Hamas, who lives in exile in Damascus. He was thought of as the natural successor to Yassin and still leads the group's political bureau. His authority was briefly challenged by Rantisi, who sought to control the group's military wing, the Izz al-Din al-Qassam Brigades.

Mr Mashal is considered by Israel to be the director of the group's terrorist attacks. He negotiated the ceasefire between Hamas and Israel last February. He was poisoned by the Israeli secret service in Jordan in 1997 but survived after King Hussein forced Israel to send an antidote. Despite today's victory, it is considered is too dangerous for him to return to Gaza.

Dr Mahmoud al-Zahar, a 60-year-old surgeon and the former personal doctor to Yassin, was named, in secret, as the Gaza leader of Hamas after the killing of Rantisi in April 2004.

Best known as a severe, eloquent spokesman of the group, Dr Zahar is a hardliner who was severely injured in an airstrike on his home in September 2003 in which his son was killed. During the recent election campaign, he was number nine on the party's list of 62 candidates.

Ismail Haniya was the leading parliamentary candidate for Hamas. He presented the group's public face during the campaign, appearing in televised messages.

Mr Haniya was expelled from the Palestinian territories to Lebanon in 1992 and is a long-serving member of the group's political bureau. He is regarded as the leader of the more practical wing of the group and has acted as a go-between with the Palestinian Authority. He has survived an assassination attempt. Either Dr al-Zahar or Mr Haniya are likely to become Hamas's first Prime Minister.

Below this triumvirate, the structure of Hamas is unclear, although Said Siyam and Hassan Yousef, two leading spokesmen, are prominent figures in the movement.

Said Siyam is thought to the group's third most senior figure in Gaza. A teacher and former protege of Rantisi, he emerged as a spokesman for Hamas in early 2004. According to Ha'aretz, the Israeli newspaper, Mr Siyam has been put in charge of contacts between Hamas and other political groups in Gaza, including Fatah and Islamic Jihad.

Hassan Yousef, the leader of Hamas in the West Bank, is the spokesman of the moderate wing of the group. A 50-year-old who was imprisoned in Israel last year, he was the former head of the Zakat, charity wing of al-Quds University and has spoken openly of a truce with Israel. Mr Yousef, who is also known as Abu Masab, snuck into the Old City of Jerusalem during the election campaign to worship at the al-Aqsa Mosque.

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