Two US nationals working for the CIA in Afghanistan were killed in an ambush at the weekend, the American intelligence agency has said in a rare statement. William Carlson and Christopher Glenn Mueller were both working under contract for the agency, "tracking terrorists" in the east of the country, near the border with Pakistan. The statement said that the agency had decided releasing the names of the dead men would not compromise ongoing operations. They died near a village called Shkin in Paktika Province. **'Bin Laden' territory*** It is unclear whether the men were killed during a period of fighting at the weekend in the same region between US-led troops and fighters, which began on Saturday morning. The Taleban fighters, which ruled Afghanistan until the US launched military action in 2001, and members of al-Qaeda reportedly continue to mount attacks in the inhospitable border region. The CIA did not provide details of the circumstances in which Carlson and Mueller died. The two men were veterans of military special operations forces, the CIA said, and working for the agency's Directorate of Operations, which conducts clandestine intelligence-gathering and covert operations. **PHOTO CAPTION*** A Muslim man prays along the roadside on the second day of Ramadan in Kabul, Afghanistan on Tuesday, Oct. 28, 2003. (AP Photo/Richard Vogel)