Kenyan police are hunting for a British woman who has been using the identity of the widow of one of the suicide bombers who attacked London's transport system, an official said Thursday.

Police suspect that she is fundraising for a terrorist group, said the official who spoke on condition of anonymity because he was not authorized to release the information.

The suspect has been using a number of identities, including those of Samantha Lewthwaite and Natalie Faye Webb, the official said. Lewthwaite is the widow of Jermaine Lindsay, one of the suicide bombers who killed 52 commuters in multiple bombings of London's transport system on July 7, 2005. British newspapers report that Faye Webb is the victim of identity theft.

The official said he cannot confirm if the woman is Lewthwaite herself. Police are working closely with Scotland Yard on the case, he said.

Lewthwaite's father, a builder from the town of Aylesbury near London, said that he and the wider family had not heard "for some time" from his daughter.

"I just wish she would get in touch with us," Andy Lewthwaite, 57, told The Sun newspaper. "Samantha would not be involved in anything to do with terrorism. She was badly affected by what happened before and would have nothing to do with it. I am sure of that."

The police official said the woman is suspected to be part of a cell that had been planning to bomb the Kenyan coast in December in retaliation for the Kenyan military incursion into Somalia.

Kenya sent troops across the border in October after a series of attacks by Somali gunmen on Kenyan soil. The Kenyan government blamed the attacks on the al-Qaida-affiliated Somali militant group al-Shabab.

Al-Shabab threatened to carry out suicide bombings in retaliation, although it has not done so thus far. But Kenya has been hit by a number of grenade and small arms attacks. Police said recently they suspect the killings of over 30 civilians in the past five months were orchestrated by al-Shabab or its sympathizers.

In January, Kenya police announced that they had thwarted a major terror attack by al-Shabab over the Christmas vacation. On the same day, Britain warned its citizens in Kenya to be extra vigilant because terrorists could be in the final stages of planning an attack.

The police official said they suspect the British woman is a member of the cell that was planning the attack. Other members allegedly include a British man, Jermaine Grant, sentenced to three years in prison for immigration offenses and lying to a government official about his identity. Grant is also charged with conspiring to commit a felony and possessing explosive materials.

Prosecutors say Grant is linked to al-Shabab but his lawyer Chacha Mwita dismissed the allegations and said his client has not told him anything about "a European woman".

The other suspected member of cell, according to the police official, is Aboud Rogo, an Islamic preacher who was arrested in January during a raid at his coastal home. Police say they recovered a cache of guns, ammunition and detonators there but Rogo's family say police planted the weapons.

A court released Rogo on bail last week and his lawyer Mbugua Mureithi challenged the police to produce evidence linking his client to a terrorist cell. Mureithi said the allegations were part of "smear campaign" against his client.

"Police have a big opportunity to prove their accusations against my client in court," Mureithi said.
Rogo was acquitted on murder charges for the 2002 bombing of a tourist hotel which killed more than dozen people and attempt shoot down an Israeli jetliner. He is also facing separate charges of being a member of al-Shabab, which has been outlawed in Kenya.

So far al-Shabab's biggest attack on foreign soil has been the July 2010 suicide attacks in Kampala, Uganda which killed 76 people watching the World Cup final. Al-Shabab said the bombings were in retaliation for the presence of Ugandan troops in Somalia.