WASHINGTON, March 12 (Reuters) - A U.S. military refueling aircraft crashed in western Iraq on Thursday, in an incident U.S. Central Command said involved another aircraft but was not the result of hostile or friendly fire.

The United States has deployed a large number of aircraft into the Middle East to take part in operations against Iran and the incident highlights the risk of operations, even over friendly skies.

In a statement, U.S. Central Command said it was carrying out rescue efforts after the U.S. KC-135 refueling aircraft went down. The second aircraft landed safely.

“The incident occurred in friendly airspace during Operation Epic Fury,” the statement said, using the military name of the U.S. operation against Iran.

A U.S. official, speaking on the condition of anonymity, said the other aircraft involved in the incident was also a KC-135 and the one that crashed had as many as six service members on board.