an Su-25 fighter jets fired on an unarmed U.S. Air Force Predator drone in the Persian Gulf on November 1, the Pentagon disclosed on Thursday.

　　The incident, reported first by CNN, raised fresh concerns within the Obama administration about Iranian military aggression in crucial Gulf oil shipping lanes.

　　The drone was on routine maritime surveillance in international airspace east of Kuwait, 16 miles off the coast of Iran, U.S. officials said. The Predator was not hit.

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　　"Our aircraft was never in Iranian airspace. It was always flying in international air space. The recognized limit is 12 nautical miles off the coast and we never entered the 12 nautical mile limit," Pentagon Press Secretary George Little said in responding to questions from reporters after CNN reported the incident.

　　Little said the United States believed this was the first time an unmanned aircraft was shot at by the Iranians in international waters over the Gulf. In December of 2011, a U.S. surveillance drone crashed in eastern Iran. Iranians claimed to have shot it down, and created a toy model of the drone to celebrate its capture.

　　Little stopped short of calling the incident an act of war although the Pentagon was concerned.

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