London: Security chiefs in the UK fear that al Qaeda will soon discover the identity of the double agent who foiled their underwear plot.
M15, UK`s internal counter-intelligence and security agency, fear that militant Islamists will try to take revenge from the British spy.
The agent was a British passport holder of Saudi heritage and volunteered to take part in a suicide mission, but instead escaped with an underwear bomb designed to blow up a US airliner.
A former security official told The Telegraph that although the mission to penetrate AQAP was a success, the agent would never be able to take part in another covert operations ever.
The official also said that the agent could be relocated outside the Middle East and also be provided with a new identity.
The AQAP is currently the ``greatest operational threat`` to Britain and America, according to senior Whitehall sources.