The baby son of Shamima Begum, a teenager who left London when she was aged 15 to join the Islamic State in Syria, has died, the BBC reported on Friday, citing the Syrian Democratic Forces spokesman.
Begum was stripped of her British citizenship in February.
The family's lawyer said earlier on Friday that there were strong but as yet unconfirmed reports that Begum's son had died.
This is Begum's third child to die in Syria. Her previous two children died due to poor nutrition and the lack of medical care, The Times reported.
Sky News, citing government sources, said Begum could have her citizenship revoked because she was a dual British-Bangladeshi national.
Britain's Home Secretary Sajid Javid said he would "not hesitate" to prevent the return to Britain of anyone who has supported terrorist organizations aboard.
In 2015, Begum ran away from home with Amira Abase and Kadiza Sultana, who were her schoolmates at Bethnal Green Academy in eastern London.The three young women went to join ISIS and marry radical Islamic militants. They have not contacted their families since 2016.
Sultana was reportedly killed in a Russian air strike. Abase married Australian citizen Abdullah Elmir, whom Australian Intelligence believe was killed in a coalition airstrike. Begum said that she met with Abase and she is still alive.
While radical Islamic movements such as al-Qaeda and the Muslim Brotherhood attracted Muslims from all parts of the world, ISIS is unique since it used social media and the Internet to attract Western Muslims – usually of a young age – to join their ranks and take part in living up to their purported Islamic ideals.
Begum said she does not regret joining ISIS and that the horrors she has seen in Syria have not made her rethink her values.