A British man believed to have carried out a suicide bombing in Iraq for the so-called Islamic State was a former Guantanamo Bay detainee paid £1m in compensation from the British government.

The bomber, named by the group as Abu Zakariya al-Britani, is said to have detonated an explosives-filled vehicle in a village south of Mosul.

The 50-year-old, also known as Jamal al Harith or Jamal Udeen, was suspected of terrorism by the US but freed from Guantanamo in 2004 after lobbying by the British government.

On his return, his solicitor said he was treated in a "cruel, inhumane and degrading manner" and would be seeking answers "for the injustice which he has suffered".

He reportedly alleged torture and received £1m in compensation after his release, along with four other Britons.

In October 2015, concerns were raised when it was claimed he had travelled to join IS fighters in Syria in early 2014.

He was born Ronald Fiddler, before turning to Islam in the 1990s and changing his name.

The former website designer of Jamaican origin travelled to the Pakistani city of Quetta in 2001 for what he claimed was a religious holiday.

He had said he tried to enter Iran when the US invaded neighbouring Afghanistan, but was captured and imprisoned by the Taliban on suspicion of being a British spy.

He had been away from his Manchester home for three weeks when he was captured by US forces, reportedly while being held in Kandahar jail.

At the time of his release, his family said he was a gentle, quiet man who rarely spoke of his faith unless asked, and a devoted father-of-three.

After four years learning Arabic and teaching English at Khartoum University in Sudan, he seemed happy enough to return home, marrying and setting up a computer business with his wife.

His brother identified him as the man equipped with explosives in an IS propaganda video.

Fiddler's wife, Shukee Begum, reportedly took her five children to Syria to try to "speak some sense" to her husband in August 2014.

The then 33-year-old from Manchester told Channel 4 News a year later that she had wanted her husband to be with their children, including a four-week-old baby whom he had not seen before.

Despite Fiddler's decision to join IS, Ms Begum insisted that her husband of 11 years was a "family man", adding: "I've always known him to be a good man with good characteristics.

"For me to take the children to see him and then come away from there that would have been more powerful than anything else I could have said at the time."