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 is facing a jail after he was found guilty of trying to join Islamic State in Syria to fulfil his ambition of becoming a martyr.
Six thieves who stole articulated lorries and their hauls, including £200,000 worth of chocolate, have been sentenced to more than 27 years.
The 83-year-old, best known for his role in the Oscar-winning film Doctor Zhivago is being cared for by his son, his agent said.