The so-called British " White Widow " Sally Jones had reportedly been killed by a US drone strike in Syria .
US spy chiefs are said to have told their counterparts at MI6 that the Islamist militant, who left Kent to join Isis in 2013, was killed close to the border between Syria and Iraq in June.
A US Air Force Predator strike reportedly took her out as she was attempting to flee Raqqa – which is currently the subject of intense fighting as Isis are driven back by coalition forces.
She is believed to have been heading to the town of Mayadin, one of the few remaining Isis strongholds, when she was killed.
A Whitehall source told The Sun: “The Americans zapped her trying to get away from Raqqa. Quite frankly, it’s good riddance."
The newspaper reported that the successful strike had previously been kept quiet over fears it may have also killed her 12-year-old son Jojo.
But it is often impossible to verify the deaths of jihadis in drone strikes with many reappearing months after their deaths were reported to the media.
US intelligence chiefs have said they are not 100 per cent certain that she is the one was who killed as it is impossible to retrieve DNA evidence.
Jones, who has been dubbed the "White Widow" by the British media, left Chatham in Kent with her son in 2013 to join the "caliphate" in its early days.
When she got there she was married to Junaid Hussain, a British-Pakistani hacker who was killed in a drone strike in 2015 .
In July the wife of a British Isis fighter, Aisha, told Sky News she had met Jones while in Isis controlled territory – she had since fled to a Kurdish refugee camp – and said she was unhappy and wanted to come home.
But Aisha said Jojo had refused as he had become brainwashed and was taking part in the execution of prisoners .
She said: "She was crying and wants to get back to Britain but Isis is preventing her because she is now a military wife.
"She told me she wish to go to her country."
Jones is understood to be a high priority on the Pentagon 's "kill list" as she is believed to be one of the terror group's top recruiters and the mastermind behind several terror plots. She was supposedly behind the plot to assassinate the Queen during the 2015 celebrations of the 70th anniversary of VJ day in London.
US intelligence officers also blame her for publishing a list of 1,300 US military personnel's details, believed to have been hacked by her husband, for Isis militants to target.
In 2016, she reportedly called on women in London, Glasgow and Cardiff to carry out terror attacks during the holy month of Ramadan.