Progress in Nairobi attack investigation

Kenyan officials are making headway in their probe into the deadly attack at the Westgate Mall.

This picture shows a house in Bromhof which, according to witnesses, was rented by Samantha Lewthwaite for three months. Picture: AFP

PRETORIA - Kenyan officials say investigators have recovered a vehicle believed to have been used by the terrorists who attacked Nairobi's Westgate Mall on Saturday.

The news comes as the Al-Qaeda linked al-Shabaab militants threatened more attacks against Kenya when taking to social media this morning to mock the country after the attack in which 67 people were killed.

Meanwhile, Unisa criminologist Henry Fouche says Interpol's Red Notice issued against terror suspect Samantha Lewthwaite is one of the most effective methods to catch an international fugitive.

The global policing body issued the arrest warrant on Thursday after a request by Kenyan authorities.

It has been widely reported, but with no official confirmation, that Lewthwaite was involved in the Nairobi mall massacre.

She is however wanted in Kenya for charges related to possession of explosives dating back to 2011.

The police forces of nearly 200 countries have been placed on alert and asked to be on the lookout for Lewthwaite.

Fouche says it should become difficult for Lewthwaite to travel.

"With 198 police forces and all of them controlling their own country's border posts and ports of entries and exits and then putting this onto their electronic systems it's going to be virtually impossible for a person to not be picked up."

Lewthwaite was recorded leaving South Africa in 2011 on a fraudulently obtained South African passport which was subsequently cancelled.