From leafy Buckinghamshire to suspected involvement in the Nairobi shopping centre terror attack, Channel 4 News looks at the life of Samantha Lewthwaite.

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Mystery still surrounds the identities of the Westgate shopping centre attackers, but amid the conflicting reports are suggestions that the group is being led by a white British woman.

This has increased suspicions that Samantha Lewthwaite, the wife of 7/7 bomber Jermaine Lindsay (both pictured, above), is involved in the attack.

'Lethal'

The 29-year-old Briton, dubbed the "White Widow", is understood to be in east Africa, and is an alleged member of al-Shabaab.

She had a very great personality. She didn't have very good confidence. Councillor Raj Khan

Eyewitnesses have said there was a female ringleader to the group of 10 to 15 terrorists that stormed the upmarket Nairobi shopping centre on Saturday afternoon.

Frank Musungu told the Daily Nation newspaper that the attackers were "young" and that "the woman appeared to be lethal".

On Monday, Kenyan Foreign Minister Amina Mohamed told the US PBS Newshour television show that a British woman was among the militants, as well as "two or three Americans". She said the woman had been involved in attacks "many times before". Her claims have not been confirmed by the Kenyan or British governments.

A British security source has said, however, that it is a "possibility" that Lewthwaite is directly involved.

Al-Shabaab, the Somali-based group behind the attack, in an interview with Channel 4 News, denied reports that Samantha Lewthwaite was among the attackers.

"We don't send our women on to the battlefield," al-Shabaab spokesman Sheikh Ali Dhere said. "I am saying to you we do not use women on the battlefield."

Al-Shabaab has also dismissed Ms Mohamed's suggestions about the nationalities of militants.

"Those who describe the attackers as Americans and British are people who do not know what is going on in Westgate building," al-Shabaab's media office said.

Samantha Lewthwaite, wife of July 7 bomber Jermaine Lindsay, is suspected to be involved in the Westgate mall attack

From Aylesbury to Somalia

Lewthwaite was born in Banbridge, County Down, in 1983 - the daughter of a British Army soldier. She moved to Aylesbury at the age of two and converted to Islam at the age of 15.

Councillor Raj Khan, whose family knew Lewthwaite's family socially in Aylesbury, said: "She was an average, British, young, ordinary girl. She had a very great personality. She didn't have very good confidence."

She married Jermaine Lindsay in 2002, before he went on to kill 26 people when he blew himself up in the 7 July 2005 attacks in London

At the time, Lewthwaite condemned her husband's actions. She went on to marry Habib Ghani, another terror suspect who was reported to have been killed by al-Shabaab gunmen earlier this month.

The mother-of-three is known to be in east Africa and is wanted by Kenyan police over her alleged links to al-Shabaab. It was reported that she crossed the border from Kenya into Tanzania with her three children on 26 December 2011.

In March 2012, Kenyan authorities said they believed Lewthwaite, now wanted for alleged links to a plot to bomb hotels and restaurants on Kenya's coast, had fled to Somalia.

Lewthwaite's alleged accomplice in the plot, Jermaine Grant, is currently on trial in Kenya over his alleged involvement. In August 2013 she was named as a suspect in a grenade attack in Mombasa.

Media reports suggested on Tuesday that a white female member of the militant group had been killed in the attack. If true, it will mark the end of an extreme journey from the home counties to militant extremism.