Four crew members have died after a US military refuelling aircraft crashed in western Iraq, officials said.

The KC-135 plane with six crew members on board went down in western Iraq at around 2pm on 12 March, US Central Command (CENTCOM), which oversees US military operations in the Middle East, said in a statement on Friday.

Rescue efforts for the other two crew members continue.

The identities of the dead service members are being withheld for 24 hours after next of kin have been notified.

The plane crash “was not due to hostile fire or friendly fire”, CENTCOM said, echoing an earlier statement on the incident which involved another aircraft that landed safely.

A US official, speaking on condition of anonymity, told the Reuters news agency the other aircraft was also a KC-135 refuelling plane.

The circumstances of the incident were under investigation, CENTCOM added.

An umbrella group of Iranian proxies called the Islamic Resistance in Iraq claimed responsibility for downing the plane on Thursday. But the group previously made false claims about attacks during the Iran war.

The US military has used the KC-135, built by Boeing in the 1950s and early 1960s, for more than 60 years to refuel aircraft mid-flight, allowing them to carry out missions without having to land.

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