International alert on woman

The worldwide alert was issued by Interpol at the request of the Kenyan authorities.

It relates to charges of possessing explosives and conspiracy to commit a felony dating back to December 2011, and it makes no mention of the Nairobi shopping mall attack, despite intense speculation linking her to the incident.

A Red Notice – or internationally wanted persons alert – notifies police forces around the world that an individual is wanted by an Interpol member state and requests the suspect is placed under provisional arrest pending extradition.

Interpol secretary general Ronald Noble said: “By requesting an Interpol Red Notice, Kenya has activated a global ‘tripwire’ for this fugitive.

“Through the Interpol Red Notice, Kenyan authorities have ensured that all 190 member countries are aware of the danger posed by this woman, not just across the region but also worldwide.”

Lewthwaite – who is believed to use the alias “Natalie Webb” – had previously only been wanted by the Kenyans at national level for the possession of a fraudulently obtained South African passport.

The 29-year-old, who converted to Islam as a teenager, was married to Jermaine Lindsay, one of the four suicide bombers who carried out the July 7 attacks in London in 2005.

Initially she said she was horrified by the attack, but in 2009 she disappeared with her three children and for the past two years has been on the run in East Africa after allegedly plotting to attack Western targets in Kenya

Reports that one of the al Qaida-linked militants who carried out the Westgate attack was a woman has prompted intense speculation that she was involved.

Al-Shabab, the Somali group responsible, has denied the claims but the Kenyan authorities have said forensic experts are working to establish if any of the attackers was female after receiving intelligence that a British woman was involved.

Mr Noble said her case highlighted the “invisible threat”’ posed by terrorists and criminals travelling internationally using illicit passports: “Every year hundreds of millions of individuals are boarding international transport and crossing borders without having the authenticity of their travel or identity document checked.”