U.K. source says possible that London bomber's widow involved in Nairobi attack

LONDON (Reuters) - A British security source said on Tuesday it was a possibility that the widow of a suicide bomber who attacked London in 2005 was involved in the siege of a Nairobi shopping mall where Islamist fighters killed at least 62 people.

When asked about reports that Samantha Lewthwaite, dubbed the "white widow" by the British media, was directly involved in the attack in Kenya, the source said: "It is a possibility. But nothing definitive or conclusive yet."