By ITV News Washington Correspondent Robert Moore
I think the Americans see a perfect storm brewing in the Middle East - really a war within a war - as various Jihadi groups fight each other for relevance and supremacy.
The concern in the US for counter-terrorism groups is that either Isis or its rivals in terms of al-Qaeda affiliates might seek to gain notoriety and new followers by attacking the US home land.
I don't believe there's a specific threat the US intelligence has intercepted.
But there is alarm here that some of these groups have gained deep technical knowledge of bomb-making as well as access to European followers - those are individuals who may not need a US visa and who with relative ease could get onboard a US-bound airliner.
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Travel industry chiefs have called for universal safety standards to be introduced across Europe, to help prevent future tragedies.
The tragic deaths of two children on a Thomas Cook Corfu holiday in 2006 could lead to a crisis of confidence for the travel industry.
Sunny spells for tomorrow, although the further we go into the weekend then we will see outbreaks of rain moving south eastwards