LONDON – The British woman dubbed the "White Widow" was at the centre of a worldwide hunt on Friday after Interpol issued an international notice for her arrest in the wake of the Kenya shopping mall attack.

Samantha Lewthwaite, a 29-year-old Muslim convert, was married to Germaine Lindsay, one of four Islamist suicide bombers who attacked the London transport network on July 7, 2005, killing 52 people.

The Interpol red notice issued Thursday at Kenya's request says the mother-of-three is "wanted by Kenya on charges of being in possession of explosives and conspiracy to commit a felony dating back to December 2011."

The notice did not specifically mention the deadly four-day mall siege in Nairobi by Somalia's Al-Qaeda-linked Al-Shebab movement,

However it follows widespread media speculation over Lewthwaite's possible role in the attack which left 67 victims dead, a toll expected to rise as more bodies are discovered.

Kenya's foreign minister said a British woman was among the Westgate Mall attackers although President Uhuru Kenyatta later said the reports could not be confirmed.

Interpol issued four colour photographs of Lewthwaite along with the arrest notice. One shows her with long dark hair and pouting at the camera, while the other three show her wearing the Islamic headscarf in various poses.

Interpol's notice, which requires member states to detain the suspect pending extradition, said Kenyan authorities wanted other member nations to be "aware of this danger posed by this woman, not just across the region but also worldwide."

It said Lewthwaite had previously only been wanted "at the national level for alleged possession of a fraudulently obtained South African passport."

Britain's Metropolitan Police and Foreign Office refused to comment, saying it was a matter for Interpol and the Kenyan authorities.

The global hunt was launched as Kenya on Thursday began burying the victims of the mall massacre by Islamist gunmen, as police pleaded for patience while searchers combed the charred rubble of the devastated complex for dozens still missing.

An 'average' girl

The daughter of a British soldier, Samantha Louise Lewthwaite professed herself appalled when her Jamaican-born husband detonated a rucksack full of explosives and blew himself up on a London Underground train at Russell Square station in 2005, killing 26 people.

She was pregnant with their second child at the time.

"I totally condemn and am horrified by the atrocities which occurred in London," she said, describing Lindsay as "a good and loving husband and a brilliant father, who showed absolutely no sign of doing this atrocious crime".

Lewthwaite had met Lindsay in an Internet chat forum when she was 17, having converted to Islam two years earlier.

Described as a bubbly teenager, schoolfriends said she had an ordinary upbringing, first in Northern Ireland and then in the market town of Aylesbury, northwest of London.

Britain's press has been fascinated by Lewthwaite's story, and The Sun on Friday ran the headline "Angel-faced British girl who last night became World's Most Wanted" across its front-page.

The paper also reported that she was being probed by the FBI.

Investigations have begun to lift the veil on Lewthwaite's shadowy movements since the London bombings.

South Africa said on Thursday that Lewthwaite had gained a South African passport using the assumed identity Natalie Faye Webb and that the document was cancelled in 2011.

She had first entered the country in 2008. She was accompanied by her three children, a girl and two boys, who would now be roughly aged between seven and 12.

Media reports this week cited credit records as showing that "Natalie Faye Webb" had at least three addresses in Johannesburg and ran up debts of $8,600 (6,400 euros).

Two neighbours in the leafy Johannesburg suburb of Bromhof told AFP they recognised Lewthwaite's picture.

Herbie Ullbricht, 69, who lived two houses away from her address cited in credit reports, said the woman lived there in "2010 or 2011" with her three children, and she was always dressed from head to toe in a hijab.

'Semi-mythical status'

Earlier this month Kenyan authorities accused her of working with another suspected British Islamist, Jermaine Grant, who is on trial in Kenya accused of links to Al-Shebab and of plotting attacks.

Grant was arrested in December 2011 in the port city of Mombasa with various chemicals, batteries and switches, which prosecutors say he planned to use to make explosives.

It is believed Lewthwaite was involved in the alleged plan to bomb a number of tourist resorts on Kenya's coast and has been on the run for months, with reported sightings of her in Somalia.

Raffaello Pantucci, a terror expert at Britain's Royal United Services Institute, said Lewthwaite had acquired a "semi-mythical status".

"I don't think we've had any concrete evidence of her being involved in this incident," he said. "But the fact of her being mentioned in this context is not surprising because of her connections."