Now White Widow is connected to British-born Al Qaeda bomb maker Mother-of-four from Buckinghamshire converted to Islam at 17-years-old Married to London bomber Germaine Lindsay before disappearing in 2007 Believed to be working for experienced Al Qaeda bomb maker Habib Ghani She has built up web of contacts between Somalia, Pakistan, UK and Africa By Rebecca Evans and Duncan Gardham The fugitive "white widow" of a 7/7 London bomber was a key link between Al Qaeda terrorists in Pakistan and their fighters in East Africa, it has emerged. Muslim convert Samantha Lewthwaite, who was married to Kings Cross bomber Germaine Lindsay, spent two years working for the deadly extremist organisation in South Africa using a false name. Investigators in Britain and Kenya have now established that the Home Counties mother-of-four has been working with a key British-born bomb maker who had trained with Al Qaeda in Pakistan. Grenade attacks: Samantha Lewthwaite is still on the run while working to help finance militant group, Al Shabaab Lewthwaite's role was to channel money raised in the UK and elsewhere to terror cells in Somalia. A security source said: "We are now clearer about the role Lewthwaite has been playing for Al Qaeda and her links with this bomb maker. She seems to have spent two years building up a network that spans the UK, South Africa, Pakistan and Somalia. Lewthwaite, 29, a soldier's daughter from Aylesbury, Buckinghamshire, has been on the run in East Africa after police foiled a Christmas bomb plot against Western tourist targets in the Indian Ocean coastal resort of Mombasa in 2011. Police now believe she has been working with experienced Al Qaeda bomb maker Habib Ghani. Sources said Ghani, from Hounslow, West London, gained bomb-making experience in Pakistan. He is understood to have a Pakistani father and a Kenyan mother and left Britain several years ago. Hiding: The Serena Beach Resort in Mombasa where Samantha Lewthwaite is believed to have previously rented an apartment Lewthwaite fled with her young children and was initially thought to have crossed the border into lawless Somalia where she was being sheltered by Al Qaeda affiliate Al Shabaab. However, there have been recent reports she may have returned to Mombasa. A Kenyan police source said: "We believe she is back in Mombasa but because she wears a full Muslim veil, she is difficult to spot. We have identified her as a blue-eyed woman in a hijab and believe she is active on Twitter and still working as a fundraiser for Al Shabaab. In December 2011, she was arrested and let go in mysterious circumstances after Kenyan police picked up her British accomplice Jermaine Grant close to a make-shift bomb factory. Grant, 30, from Brixton, south London, and Lewthwaite were both charged with possessing bomb-making materials and of planning to cause loss of "innocent civilian lives." Caught: British-born Jermaine Grant, 30, in cuffs and flanked by guards as he is held on terror charges in Mombasa, Kenya He will briefly appear in court on Mombasa on Wednesday. Last month, Scotland Yard anti-terror officers were due to fly to Kenya to give evidence in Grant's trial. But police received a tip-off that Lewthwaite and other Al Shabaab terrorists were planning to attack the court and free him, so his trial will now take place in a high-security court inside a prison. Lewthwaite, who also uses the Muslim name Sherafiyah, converted to Islam at the age of 17 and married Lindsay in 2002 after meeting him on the internet. She was seven months" pregnant when Lindsay, a Jamaican convert from Huddersfield, West Yorkshire, killed 26 people when he blew himself up on a Piccadilly Line train in July 2005. Bombers: Germaine Lindsay, Samantha's ex-husband, pictured centre before he blew himself up on a Piccadilly Line train in July 2005 Devastation: The Piccadilly Line train after Germaine Lindsay detonated the bomb between King's Cross and Russell Square tube stations British security services have so far failed to explain how she slipped off the radar, travelled to East Africa on a stolen passport, and became, as police believe, an integral member of Al Shabaab. Since her disappearance, Lewthwaite has been linked to a spate of grenade attacks in Mombasa, including one on a packed pub last year which killed three people, including a nine-year-old boy. There are also reports she is using Twitter to bolster support for an all-female suicide squad in East Africa. She is known as "dada mzungu" - Swahili for white sister - and is described as serving "Allah as his female soldier" and who "commands her all-female mujahid terror squad and conducts operations against the kuffar [non-Muslims]." Grant is also facing charges for trying to sneak into Somalia disguised as a Muslim woman in 2008.