Mohammed Emwazi, also known as Jihadi John, was "evaporated" by a Hellfire missile fired from a US Reaper drone after British intelligence analysts located him in the Islamic State of Iraq and Syria (ISIS) headquarters of Raqqa.
Kuwait-born British citizen Jihadi John secretly fathered a son who is automatically entitled to British citizenship and could be brought to live in the UK, The Telegraph reported.
It has emerged that the Home Office will be powerless to stop Jihadi John's Syria-born son coming to live in Britain at some point in the future, the report said.
The identity and nationality of the boy's mother is not known, but Home Office rules make it clear that he is already regarded as British, stating, "British citizenship may descend to one generation born abroad. So a child born abroad to a parent who is British...will automatically be British by descent."
It means he would be entitled to a British passport and could come to live in the UK, though his mother, if she is from outside the EU, would have to apply for a visa to be allowed into the country, the report said.
Although one or two officials in Washington are counselling caution, there is now an overwhelming consensus that Jihadi John was killed in the drone strike along with a sympathiser - possibly his driver - as their car hurtled through the Syrian town of Raqqa.
Gradually details of how the British Jihadist was tracked down and then attacked by a drone have started to emerge. A British drone, operating from Lincolnshire, helped track Jihadi John, although what are believed to have been the fatal shots were fired by the Americans.
According to one report he was tracked for six weeks before the decisive strike was made. Jihadi John participated in the videos showing the murders of US journalists Steven Sotloff and James Foley, aid worker Abdul-Rahman Kassig, British aid workers David Haines and Alan Henning, Japanese journalist Kenji Goto, and a number of other hostages.
In mid 20s, Emwazi, was identified as the mysterious knife-wielding man in the gruesome ISIS execution videos. He was dubbed Jihadi John by the British press because he belonged to the group of English-speaking militants that former hostages dubbed "the Beatles".