US officials believe that the Nusra Front, al-Qaeda's affiliate in Syria, has been working with its Yemen affiliate, AQAP, to carry out operational testing of new bomb designs in Syria.
The new explosives the bombmakers are trying to design include non-metallic bombs, ABC News reported.
There are also concerns that US and Europe-bound planes could be targeted by foreign fighters with Western passports who spent time fighting for Islamist groups attempting to overthrow the regime of Syria's president Assad.
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A man's body has been discovered in the sea off the Kent coast.
Cooler and cloudier for much of the UK with showers or longer spells of rain.
Donald Trump has said North Korea showed disrespect to its major ally China after it fired a short-range ballistic missile.