Kidnappers holding U.S. Marine Lt. Col. William R. Higgins said in a statement released Monday they have sentenced him to death as a spy for Israel. ``We have issued the irrevocable sentence to execute this American spy,'' said the typewritten Arabic statement signed by the Organization of the Oppressed on Earth. ``The spy has been turned over to those responsible for executing this just and revolutionary verdict,'' said the statement delivered to the Beirut newspaper An-Nahar. The statement did not give a date when the sentence was to be carried out. A photocopy of a photograph purporting to show Higgins in a dark sweater was pasted to the bottom of the 15-line statement. Captors of foreign hostages in Lebanon usually provide a photograph to authenticate their statements. Higgins, 43, of Danville, Ky., was head of a 76-man observer group attached to the U.N. peacekeeping force in south Lebanon when he was kidnapped near the southern port city of Tyre on Feb. 17. ``It has been proven by clearcut evidence that he and his American team of observers are guilty of providing the Zionist enemy with accurate and detailed military and security information about our resistance fighters, their positions, movements, supply routes and the quantity and quality of their weaponry,'' the statement said. It said the decision to kill Higgins was a retaliation for Israeli attacks against ``our people in occupied Palestine'' and predominantly Shiite south Lebanon. The statement also said Higgins was sentenced to die in ``revenge for the blood of the martyrs of the latest Israeli raid'' on a Palestinian guerrilla base nine miles south of Beirut. Nine guerrillas were killed Friday in the Israeli attack. An Israeli officer also died. Fifteen foreigners are missing and presumed kidnapped in Lebanon. They are nine Americans, three Britons, one Irishman, one Italian and a Swiss. The longest held is American Terry A. Anderson, 40, chief Middle East correspondent for The Associated Press, who was kidnapped March 16, 1985. Higgins, 43, a decorated Vietnam veteran, is married to Marine Maj. Robin Higgins and has a 17-year-old daughter. He graduated from high school in Louisville, Ky., and from Miami University of Ohio on ROTC scholarship in 1967. He earned master's degrees in human resources management at Pepperdine Univiversity in California and in political science at Auburn in Alabama.