Airport security in the US and several EU countries has been ramped up amid fears al-Qa’ida plans to use Western jihadists as suicide bombers.
It is feared the master bomb maker Ibrahim Hassan al-Asiri, from al-Qa’ida in the Arabian Peninsula (AQAP), has developed a new explosive that could evade current security checks.
In the clearest indication yet on the new threat, US officials warned partners to focus on smartphones and shoes.
It is feared that Asiri may also have perfected a new type of shoe bomb. In 2001, the Briton Richard Reid tried to detonate explosives packed into his shoes on an American Airlines flight from Paris to Miami, but it failed to explode and Reid was later jailed for life.
Asiri is suspected of trying to develop a “body bomb” where explosives are surgically implanted into volunteers.
Travellers now face invasive physical checks and lengthy delays this summer.
Intelligence suggests that AQAP, and specifically Asiri, has linked up with the Jabhat al-Nusra jihadists in Syria and passed on bomb-making skills.
The alert centred on fears that Asiri, who was also behind the “underpants bomb” on a flight to Detroit on Christmas Day 2009, is passing on his expertise to fighters in Syria. He knows that he could be killed at any point.
US officials have demanded enhanced security for airports in Europe and the Middle East with direct flights to America. No specific plot was mentioned, but a Homeland Security official said the request was “based on real-time intelligence”.
Yesterday, France announced it was stepping up security checks at its airports, in response to the warning from the US. America is also concerned that it may not be able to prevent suspected fanatics from boarding planes after a court ruling on its “do not fly” list.
A Federal Court in Oregon last month said people should be granted greater rights to challenge their inclusion on the list.
Even though the list has not been struck out, the ruling opens the way for challenges to a system that has been a key part of the US security apparatus for nearly 13 years. It is estimated there are 20,000 people on the list – including about 500 US citizens.
Experts in America have criticised Britain and other European nations for failing to tackle the problem of young Muslims going to fight in Syria and Iraq.
Security and political experts said Britain had turned a blind eye to the threat for too long.
Hassan Mneimneh, a senior fellow at the German Marshall Fund of the United States, a think-tank, said European governments had failed to eradicate jihadism in the Arab Spring.
“There was an opportunity to marginalise jihadism, but the opportunity has passed,” he said. “To allow a place like Syria to fester was an invitation to jihadism, so it cannot come as a surprise to governments. We have an invigorated recruitment network of jihadists.
“They are recruiting people who are marginalised, radicalised and then come back and make bombs.”
Dr Nile Gardiner, director of the Margaret Thatcher Centre for Freedom in Washington DC, said recent threats were a “reflection of weak immigration policy and a failure to tackle Islamic extremism in the UK”.
But Dr Quintan Wiktorowicz, who was an adviser to Barack Obama, said: “Policy makers need to decide their top priority. If it is social cohesion, you may do one thing and if it is counter-terrorism, you may do another.”