PLO and Hamas
During the fifty years of the Israeli-Palestinian conflict, it has been claimed that the Palestine Liberation Organization (PLO), the main political organization of the Palestinians, is allied with Hamas, a Palestinian fundamentalist paramilitary and political organization, which is accused of organizing suicide bombers and other attacks against Israel.The PLO takes measures to distance itself from Hamas, but because of the widespread popular support of Hamas, the PLO has historically been reluctant to directly confront the organization. While both the PLO and Hamas share a similar goal of different treatment of Palestinians, their rhetoric, methodology, and end-goals have vastly differed at times, leading to ideological and political rifts between the two groups. Hamas has described itself as posing a challenge to the PLO's authority, and charges that many of its leaders have been arrested by the Palestinian Authority (PA).
Playing down the differences between the two organizations, Palestinian officials resist Israel's characterization of Hamas as a terrorist organization. The former Palestinian Authority Cabinet Minister Hanan Ashrawi has said "it is not up to Israel to decide or define who is our enemy. Hamas is not the enemy, it is part of the political fabric." (Jerusalem Post, July 25, 1995). The PLO may also at times see Hamas as a strategic asset for pressuring Israel. As Abbas Zakai of the Fatah Central Committee said: "[Hamas's attacks] strengthen the Palestinian position... It would be dangerous to stop these actions, because the accords will crumble if there is nothing to make Israel go forward." (Al Hayat, April 17, 1995)
Under the Oslo Accords, the PLO was obligated to refrain from incitement to terrorism and to act against terrorism. Critics charge, however, that the PLO has violated this agreement by continuing to support Hamas, which is considered a terrorist organization by the United States and the European Union. For example, PLO leader Yasser Arafat publicly praised Yahya Ayyash, the master Hamas bomb-maker who killed at least 60 Israelis, as "the struggler, the martyr" (New York Times, January 8, 1996) and "a martyr" (Jerusalem Post, July 28, 1996). On March 22, 2004, the Palestinian Authority declared an official three days of mourning for the former Hamas leader, Sheikh Ahmed Yassin, after he was killed by an Israeli Air Force airstrike.
The al-Aqsa Martyrs' Brigades, a terrorist faction of Yasser Arafat's Fatah, which claimed by Israel to be funded by the Palestinian Authority, have carried numerous attack in cooperation with Hamas against Israel targets. After these attacks, the Brigades and Hamas took joint responsibility.
List of joint terrorist attack
Israeli domestic press have asserted that they found some signs of joint activities:
Joint violent attacks
Other alleged links between the Hamas and the PLO