In the first known direct U.S. military intervention in Somalia since a disastrous peacekeeping mission that ended in 1994, U.S. aircraft attacked Islamists accused of harbouring al Qaeda suspects, a Somali government source said.
Following are some key dates in Washington's relations with Somalia in the past 15 years.
December 1992 – The United States sends 28,000 troops to Somalia at head of 'Operation Restore Hope', a U.N. military effort to quell Somalia's wartime famine.
October 1993 – 18 U.S. Army Rangers are killed when Somali militias shoot down two military helicopters. The United States later suspects the Somalis were trained by al Qaeda, and the event is dramatized in the movie 'Black Hawk Down.'
March 1994 – The United States ends its mission in Somalia.
August 1998 – Truck bombs claimed by al Qaeda kill 224 people at the U.S. embassies in Kenya and Tanzania. Suspects include Somali citizens and the United States receives reports that al Qaeda members are in Somalia.
December 2002 – The United States sends 1,300 military personnel to establish a counterterrorism unit near Somalia. Based in Djibouti, the task force is designed to hunt for militant groups in six Horn of Africa countries, including Somalia. Commanders discuss sharing security technology with regional forces and training them in counterterrorism techniques.
Early 2006 – Somali warlords form an 'Alliance for the Restoration of Peace and Counterterrorism' in Mogadishu. Experts on Somalia say the CIA is funding the group, whose members have been battling Islamic militias for control of the country.
June 2006 – Galvanising popular support with anti-U.S. rallying cries, Islamic militants take over Mogadishu and rout warlords.
Dec. 2006 – Islamists flee Mogadishu ahead of a joint Ethiopian and Somali government force which captures the capital. Diplomats say Washington gave tacit support – plus surveillance and intelligence help – to its ally Ethiopia.
Jan. 2007 – U.S. aircraft strike the southern village of Hayo, after it was believed that at least one al Qaeda suspect was sheltering there.