COMISO, Sicily (AP) _ The last American contingent has left the cruise missile base closed as part of the 1987 U.S.-Soviet nuclear arms reduction treaty.

The departure of the last 500 American servicemen on Wednesday leaves only Italian air force personnel at the former missile base, the Italian news agency AGI said. The last missiles were removed and destroyed last spring.

Italian authorities have still not decided what to do with the military air field in southern Sicily, which had been the base for the nuclear tipped missiles for 10 years.

One plan under consideration would keep it open as an Italian air force base that could support the Sigonella air base at Catania.

Comiso Mayor Salvatore Zago has been suggesting that the base be converted to civilian use, possibly as a small civilian air field. Sicilian physicist Antonino Zihichi has proposed that the government transform the base into a major international research center.