The KC-135 plane 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.
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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Seven US troops - 13 when the crew members from the crashed plane are taken into account - have been killed since the start of the US-Israeli strikes on Iran on 28 February.
So far, the war has killed more than 2,000 people, including nearly 700 in Lebanon. Israel has expanded its offensive against Iran-backed Hezbollah, with strikes hitting Lebanon's capital Beirut overnight.
It's brought a spike in oil prices, a chance to play peacemaker, and now the easing of US sanctions on Russian oil.
This latest development marks a stunning reversal of policy from the Trump administration, and a major coup for the Kremlin.
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Scott Bessent, the US treasury secretary, has played down the significance of any financial benefits for Moscow, stressing that the measures are "narrowly tailored" and "short term".
But that feels like wishful thinking from Washington, and a lot of positive spin.
According to the Financial Times, Russia has been pocketing as much as $150m a day in extra oil revenues as a result of the crisis, after the disruption to global energy supplies led to increased demand from China and India.
The lifting of sanctions means it now has a load of extra customers it can potentially sell to, and business has already begun, with Thailand announcing this morning that it's ready to buy Russian oil.
Oil was the area where the Trump administration had sought to put pressure on the Kremlin - to harm its economy in a bid to bring it to the table on Ukraine.
To a certain extent it was working. Depleted sales to India (as a result of US sanctions), combined with a drop in prices, has led to a ballooning budget deficit, by depriving the Kremlin of a vital source of income.
Russia's defence spending hadn't been impacted yet, but it was making the maths harder for Moscow to add up.
So this represents a remarkable turnaround, not only economically but diplomatically too.
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Symbolically it brings Russian oil back in from the cold, and creates further splits in the transatlantic alliance.
Europe is staunchly against any sanctions relief for Russia, with both Ursula von der Leyen and German Chancellor Friedrich Merz voicing their opposition to it in recent days. Such friction only plays into Moscow's hands.
Domestically, too, it helps the Kremlin reinforce its message to the public that it was right all along - that the world needs Russia.
"The US is effectively acknowledging the obvious: without Russian oil, the global energy market cannot remain stable," Kremlin investment envoy Kirill Dmitriev wrote on Telegram.
"Amid the growing energy crisis, further easing of restrictions on Russian energy sources appears increasingly inevitable, despite resistance from some in the Brussels bureaucracy," he added.
Moscow clearly hopes this means that the sanctions genie is out of the bottle. Depending on the direction of oil prices, it may well be right.
Madeleine Lonsdale, 18, had been racing another car at 100mph before she struck a tree in Marston, Lincolnshire, on 20 June last year, killing passengers Harrison Carter, 18, and George Stephenson, 17.
She partied "repeatedly" in the months after their deaths, frequently uploaded to TikTok and her first court appearance was delayed for two weeks because she went on a skiing trip.
On Friday she was sentenced to 14 months behind bars, having earlier pleaded guilty to two counts of causing the teenagers' deaths by careless or inconsiderate driving.
Mr Carter and Mr Stephenson had been passengers in Lonsdale's Kia Niro when the three headed to an Esso petrol station off the A1 in the early hours of the morning.
The car was travelling at 76mph when Lonsdale misjudged a bend in the 60mph road, killing both passengers almost immediately.
Lonsdale, who passed her driving test about 12 weeks before the crash, escaped with just a small injury to her wrist.
Moments earlier, Lonsdale had been racing another friend on the A1 - briefly travelling at 100mph, the court heard.
Sarah Carter said of her son, who wanted to pursue a career in law: "Harry was taken from us because Madeleine chose to speed.
"He will never be able to celebrate the amazing exam results that he achieved."
Ms Carter said it "adds insult to injury" that Lonsdale was "partying repeatedly" and "choreographing TikToks" while she planned her son's funeral.
Victoria Stephenson, George's mother, told the court: "We will never see him graduate or find a job after university.
"We didn't get to celebrate his 18th birthday with him. Instead, we had his funeral."
She said that when Lonsdale went on a skiing trip, delaying her first court appearance by two weeks, it "only added to the torment".
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John McNally, defending Lonsdale, said: "She knows that there is nothing she can say, do, to take the pain away.
"She knows it will weigh heavily on her for the rest of her life.
"Her regret for what happened is deep and … her friends will remain, and are, in her thoughts."
Lonsdale was disqualified from driving for three years.
The image shows Andrew and Mandelson, the UK's former ambassador to the US, sitting in white bathrobes with the late convicted paedophile.
The picture was among the Epstein files released by the US Department of Justice. Being mentioned in the files is not evidence of wrongdoing.
The former prince has always denied wrongdoing in relation to Epstein.
Lord Mandelson has previously denied any wrongdoing over his relationship with the billionaire paedophile and has apologised to the financier's victims.
Andrew lost his royal and military titles over his links to Epstein, who took his life while awaiting trial for sex trafficking charges in a US prison in 2019.
The former prince was arrested and released under investigation on Thursday 19 February, over allegations of misconduct in public office - something he strongly denies.
He had been arrested at Sandringham on his 66th birthday on suspicion that he shared sensitive information with Epstein when he was UK trade envoy.
The former prince has been living at Sandringham since leaving Royal Lodge in Windsor at the start of February.
Lord Mandelson was questioned by police after being arrested on suspicion of misconduct in public office at the end of last month.
He was accused of passing sensitive information to Epstein during his time as business secretary from 2008 to 2010, when Gordon Brown was prime minister.
He was released on bail and he has previously denied any wrongdoing.
William Todd, 61, has been sentenced to seven years in prison after he was found guilty of conspiracy to pervert the course of justice.
He directed the scheme from his cell using a secret mobile phone under the alias Ari Gold - the Hollywood agent played by Jeremy Piven in TV series Entourage.
Todd was given two life sentences in 2001 for the attempted murder of his former business partner Arthur de Sousa and shooting dead Mr de Sousa's bodyguard in the Berkshire village of Pangbourne.
He escaped from Winchester prison after sawing through the bars of his cell window before scaling the 30ft wall using a homemade grappling hook and rope ladder - but was caught five days later.
Todd was nearing the end of his sentence at Coldingley prison when he staged an elaborate plan to help the gang who smuggled 448kg of MDMA to Australia in the arm of an industrial digger walk free.
The organised crime group was caught after Danny Brown, 58, sent a picture of his pet French Bulldog Bob to Stefan Baldauf, 66, showing his partner's phone number on the dog tag over encrypted communications platform EncroChat.
Southwark Crown Court heard Todd brokered the plot on behalf of others, using a 46-year-old man, who cannot be identified for legal reasons, as his man on the outside to record the names of the jurors when they were sworn in for their trial.
When the jury retired to consider verdicts in June 2022, false claims were sent to Kingston Crown Court and police that named jurors had been bribed up to £20,000 to acquit the men on trial.
The jury, court staff, solicitors and barristers all initially fell under suspicion, but some of the jurors had already been discharged and names had been misspelled, so the trial continued after it was found to be a "dishonest attempt to derail the trial," said prosecutor Charlotte Hole.
After Brown and Baldauf were found guilty of drug trafficking days later, along with four other men, Sheree Avard, 41, from Woking, Surrey, was recruited in a bid to get the convictions quashed.
The court heard she called Brown's lawyer posing as the girlfriend of one of the men on the jury, who she claimed had confessed he was pressured by corrupt National Crime Agency officials to convict the men.
An image of a fake passport was also created in the name of Ioana Andrei and a woman in Romania was paid 2,000 euros to sign an official deposition, along with a corrupt solicitor in Bucharest, which was sent to the lawyer.
The statements were leaked online, claiming police and NCA were corrupt and influencing jurors.
The prosecutor said "there was a real risk of serious consequences for innocent parties", adding: "Had this been believed, jurors could have been in contempt of court or worse."
Avard and the man who cannot be named admitted conspiracy to pervert the course of justice between March and November 2022, and were jailed for 12 months, and three years and four months respectively.
Sentencing the three involved, Judge Gregory Perrins said the plot "struck at the very heart of justice".
"This was a professional, persistent and sophisticated attempt to undermine the trial and then the convictions of people involved in serious organised crime," he said.
"The intention of the conspiracy was to undermine the entire process of justice."
He said Todd had "close links" with the organised crime group and told "directed every part of the conspiracy" from his prison cell.
Steve Ahmet, senior investigating officer at the NCA's Anti-Corruption Unit, said: "This case shows the remarkable lengths that high-harm criminals will go to in order to cheat justice and why they pose the greatest corruption threat to crucial pillars of our society.
"The offenders were determined to help their criminal associates walk free but our team built a rock-solid case against them."
Brown, from Bromley, Kent, and Baldauf, from Ealing, west London, were jailed for 26 years and 28 years respectively in December 2022.