The identities have been disclosed of all six crew who died when their US military refuelling plane crashed this week.

An umbrella group of Iranian proxies, the Islamic Resistance in Iraq, claimed responsibility but US authorities have said it "was not due to hostile fire or friendly fire".

The Boeing KC-135 was in "friendly" airspace over western Iraq on 12 March when an unspecified incident involving another aircraft occurred, according to US Central Command.

The other plane landed safely, authorities said.

One of the victims, Major John A Klinner, 33, was deployed to help the Iran war effort less than a week before the crash.

"It's kind of heartbreaking to say, he was just a really good dad and really loved his family a lot - like a lot," his brother-in-law James Harrill said.

The eight-year US Air Force veteran from Auburn, Alabama, had just moved into a new home with his family, his wife Libby Klinner said in a social media post. The couple have seven-month-old twins and a two-year-old son.

Technical Sergeant Tyler H Simmons, 28, of Columbus, Ohio, was another of the six who died.

In a statement obtained by WCMH-TV in Columbus, Mr Simmons' family said his "smile could light up any room".

"His parents, grandparents, family and friends are grief-stricken for the loss of life," they added.

After the confirmation by the families of Technical Sergeant Simmons and Major Klinner on Saturday, the US Department of War officially named all the crew members who died.

The other four are:

Captain Ariana G Savino, 31, of Covington, Washington; Technical Sergeant Ashley B Pruitt, 34, of Bardstown, Kentucky; Captain Seth R Koval, 38, of Mooresville, Indiana; and Captain Curtis J Angst, 30, of Wilmington, Ohio.

The chief of the National Guard Bureau shared a picture of them all on X.

Major Klinner, Captain Savino and Technical Sergeant Pruitt were assigned to the 6th Air Refueling Wing, MacDill Air Force Base, in Florida.

The others were assigned to the 121st Air Refueling Wing at Rickenbacker Air National Guard Base, Columbus, Ohio.

"We share in the sorrow of their loved ones, and we must not forget the valuable contributions these Airmen made to their country and the impact they have left on our organization," said the Air National Guard on social media.

(c) Sky News 2026: US names the four men and two women killed in refuelling plane crash over Iraq