Here are the main events in the history of the Hamas movement, whose spiritual leader and founder, Sheik Ahmed Yassin, was killed in an Israeli airstrike on Monday:

December 1987: First Palestinian uprising against Israeli occupation erupts, and Yassin founds Hamas as an Islamic resistance movement against Israel.

1988: Hamas publishes manifesto calling for "holy war" to create an Islamic state from the Jordan River to the Mediterranean Sea, including Israel, and challenging the Palestine Liberation Organization's claim as the sole representative of the Palestinian people.

1989: Hamas militants kill Israelis in dozens of shooting attacks; Israel outlaws Hamas as a terrorist organization.

1989: Israel imprisons Yassin.

1991: Hamas forms "Izzedine al-Qassam Brigades," its military wing, for attacks against Israelis.

April 6, 1994: First Hamas car bombing kills eight in Israeli city of Afula.

April 13, 1994: First Hamas suicide bombing kills five in Israeli city of Hadera.

Oct. 19, 1994: Hamas suicide bomber blows up Tel Aviv bus, killing 22.

February-March 1994: Hamas suicide bombers blow up two Jerusalem buses, killing 45.

Jan. 6, 1996: Hamas master bombmaker Yehiyeh Ayyash killed in explosion, Israel held responsible.

February to March 1996: 47 Israelis killed in three suicide attacks in retaliation for killing of Ayyash.

September 1997: Yassin released from prison after botched Israeli attempt to kill Hamas leader in Jordan.

September 2000: Second Palestinian uprising begins.

June 1, 2001: Hamas suicide bomber blows up outside Tel Aviv disco, killing 21.

Aug. 9, 2001: Hamas suicide bomber blows up Jerusalem restaurant, killing 15.

March 27, 2002: Hamas bomber blows up Netanya hotel, killing 29.

July 23, 2002: Israel drops one-ton bomb on house of Hamas leader Salah Shehadeh in Gaza, killing him and 14 others.

Aug. 21, 2003: Hamas leader Ismail Shanab killed in Israeli airstrike.

August-September 2003: 39 killed in three Hamas suicide bombings.

Sept. 6, 2003: Yassin slightly wounded in Israeli bombing in Gaza.

March 14, 2004: Two bombers, one from Hamas, kill 10 at Ashdod port.

March 22, 2004: Yassin killed in Israeli airstrike in Gaza City.