Indian-origin dubbed 'new Jihadi John' ready to die for ISIS, says sister

London: An Indian-origin Islamic State terrorist, believed to be the masked man in ISIS' latest video who has been dubbed "new Jihadi John", is ready to die for the terror group, his sister has said.

London-based Konika Dhar had received a message from her brother Siddhartha Dhar, also known as Abu Rumaysah, last year after he had skipped bail and fled the UK with his pregnant wife and four children saying, "I'm prepared for death".

In a phone-call in October last year, he said, "Focus on the hereafter and don't worry".

Read: MI5 tried to recruit Indian-origin 'new Jihadi John' for Islamic State: Report

Konika told 'The Sunday Times', "I told him from the very beginning when he arrived in Syria and made contact that I would love him to return home and live in our house with his family."

But he said he cannot return because he believed that he would be arrested.

While the identity of Dhar as the masked man in recent ISIS video threatening terrorist strikes on Britain has not been confirmed by security services, his sister has spoken of her fears that it may be her brother.

She pleaded with British Prime Minister David Cameron not to use drones to try to kill her brother because she believes he has been brainwashed.

"I believe my brother is unwell; he needs help and needs intensive care. I think it will be harder for him to make rational decisions based on his current state of health. He has been completely brainwashed...I'm very disappointed in the person he has become, but I still love him because he is my brother. I would rather see him rehabilitated in prison in the UK than dead on the Syrian battlefield," she told the daily.

The law student paints a picture of a mild mannered Arsenal football club fan who was born and raised a Hindu before he converted to Islam and took on the names of Abu Rumaysah and Saif al-Islam.

She recalls how, during his school years, Dhar dreamt of becoming a vet.

He had a turtle, rabbit and hamster at home and helped to look after a neighbour's cat called David. She said her brother almost wept when the animal was run over by a car and killed.

Once he moved away from studies and took a series of retail jobs, his association with a childhood Muslim friend became stronger.

The 32-year-old, who also had a job selling bouncy castles, was converted by his Muslim friend who organised his "arranged marriage" in 2006 with Aisha and helped him to join Al Muhajiroun, an Islamist group banned as a terrorist organisation in 2010.

The friend, who cannot be named for legal reasons, was later imprisoned for terrorism-related offences.