Leading candidates to replace Palestinian leader Yasser Arafat:

--Ahmed Qureia, the Palestinian Parliament speaker, would replace Arafat if he exited suddenly, according to the Basic Law governing the Palestinian Authority. Qureia, 65, known as Abu Ala, underwent open heart surgery Wednesday, his second in a week. He was a main negotiator in secret talks leading to the first interim peace accord with Israel in 1993. He continues working with Israeli Foreign Minister Shimon Peres on a peace plan.

--Mahmoud Abbas, 67, known as Abu Mazen, is Arafat's deputy as head of the Palestine Liberation Organization. He also was deeply involved leading to interim peace accords. Abbas was first Palestinian leader to accept Israeli claims in parts of the Old City of Jerusalem and is considered by some Palestinians too conciliatory toward Israel.

--Jibril Rajoub, 49, head of Preventive Security in the West Bank and one of the most powerful figures there. He has had wide-ranging contacts with Israeli leaders and has participated in many negotiating sessions over security matters. Rajoub speaks fluent Hebrew from years in Israeli prisons and is considered a moderate pragmatist by Israelis.

--Mohammed Dahlan, 41, just resigned as head of Preventive Security in the Gaza Strip and is expected to become closer to Arafat as his security adviser. Dahlan, a Rajoub rival, also has represented the Palestinians in security talks with Israel. His security branch was the strongest in the Gaza Strip, making him extremely influential there.

--Marwan Barghouti, 42, is the secretary-general of Arafat's West Bank Fatah movement. He consistently backs resistance by Fatah activists against Israeli occupation. Barghouti is an accomplished speaker with a large following among West Bank Palestinians. Israel accused him of responsibility for dozens of terror attacks and arrested him April 15 during its West Bank invasion. He remains in Israeli custody.