HAMAS formed in late 1987 at the beginning of the first Palestinian Intifada (uprising). Its roots are in the Palestinian branch of the Muslim Brotherhood, and it is supported by a robust social/political structure inside the Palestinian territories. The group’s charter calls for establishing an Islamic Palestinian state in place of Israel and rejects all agreements made between the PLO and Israel. More recently, HAMAS has publicly expressed a willingness to accept a long-term cessation of hostilities if Israel agrees to a Palestinian state based on the 1967 borders with Jerusalem as its capital. HAMAS’s strength is concentrated in the Gaza Strip and areas of the West Bank.

HAMAS has a paramilitary arm, the Izz al-Din al-Qassam Brigades, which, beginning in the 1990s, has conducted many anti-Israeli attacks in Israel and the Palestinian territories. These have included large-scale terrorist bombings against Israeli civilian targets, as well as small-arms attacks, improvised roadside explosives, and the launching of rockets into Israel. While the group receives some support from foreign countries and movements, it remains independent.

In early 2006 HAMAS won legislative elections in the Palestinian territories, ending the secular Fatah party’s hold on the Palestinian Authority and challenging Fatah’s leadership of the Palestinian national movement. HAMAS continues its refusal to recognize Israel or renounce violence against Israelis and, since early 2008, has conducted one suicide bombing, which killed one civilian, and numerous mortar and rocket attacks that injured civilians. The US Government has designated HAMAS as a Foreign Terrorist Organization.

HAMAS in June 2008 entered into a six-month agreement with Israel that significantly reduced rocket attacks. Following the temporary calm, HAMAS resumed its rocket attacks, which precipitated a major military operation launched by Israel on 27 December 2008. After destroying much of HAMAS’s infrastructure in the Gaza Strip, Israel declared a unilateral cease-fire on 18 January 2009. Since 2009, HAMAS has worked to rein in attacks from other groups and enforce the cease-fire, though sporadic low-level attacks against Israeli forces along the Gaza border have continued.

In May 2010, the Israel Defense Forces intercepted a flotilla of humanitarian aid vessels bound for the Gaza Strip, which since 2007 has been under a strictly enforced Israeli blockade. The seizure of one ship led to a violent confrontation and resulted in the death of nine passengers. HAMAS publicly condemned the incident, which it characterized as a massacre, and urged international activists to continue their attempts—with additional flotillas if necessary—to break the blockade. In late August 2010, an Izz al-Din al-Qassam Brigades spokesman claimed responsibility for the shooting deaths of four Israeli settlers, an attack widely believed to be aimed at scuttling peace talks between Palestinians and Israelis in Washington.