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.

‌The Islamic Resistance in Iraq, ​an ​umbrella group of

⁠Iran-backed ​armed factions, claimed responsibility for downing

the U.S. military refueling aircraft.

The group said in a statement it had shot down the KC-135

aircraft "in defense of our country's sovereignty and airspace".

The KC-135, built by Boeing ( BA ) in the 1950s and early

1960s, has served as the backbone of the U.S. military's air

refueling fleet and is critical to allow aircraft to carry out

missions without having to land.

Since the U.S. and Israel started carrying out strikes

against Iran on February 28, seven U.S. troops have been killed.

The United States has carried out strikes against more than

6,000 targets in Iran.

Reuters ​reported on Tuesday that as many as 150 U.S. troops

have been wounded in the U.S.-Israeli war on Iran. News of the

crash comes the same day two U.S. sailors were injured after the

USS Gerald Ford suffered a ​non-combat-related fire on board.

So far the war has killed more ⁠than 2,000 people, including

almost 700 in Lebanon.