A little-known terrorist group that the US bombed in Syria was in the advanced stages of a plot to blow up airliners with explosives concealed in toothpaste, it has been reported.
The Khorasan Group, a relatively unknown Al Qaeda offshoot, was among the groups targetted by the attacks on Syria on Tuesday, that also hit Islamic State's enclave in the country.
One of the Khorasan Group's plots was to smuggle bombs on planes with non-metallic devices, including toothpaste tubes. It was in the final stages of planning the attack, a military source told CNN.
The group's plot was the reason behind the sudden decision to ban uncharged mobile phones and electronic devices on flights in July this year.
This followed the intelligence that the group was working with Yemeni bomb-makers to target airliners.
William C. Mayville Jr, director of operations for the US Joint Chiefs of Staff, said the group was in the “final stages of plans to execute major attacks against Western targets and potentially the US homeland”.
James R Clapper, the US Director of National Intelligence, said last week that Khorasan were more dangerous than IS "in terms of threat to the homeland".
They are described as hardened jihadis from Afghanistan, Yemen and Syria who are not interested in seizing land but carrying out major attacks on the West.
Its members travelled to Syria but intelligence agencies believe they were sent by al Qaeda leader Ayman al-Zawahiri to recruit Westerners already fighting there who could be more likely to get through airline and immigration security, rather than to fight Assad's forces.
“They’re in Syria but they’re not really fighting in Syria,” Michael Leiter, the former director of the National Counterterrorism Center, told NBC News.
“They’re using it as a place to find Western recruits.”
Barack Obama called them "seasoned al Qaeda operatives."
"Once again, it must be clear to anyone who would plot against America and try to do Americans harm that we will not tolerate safe havens for terrorists who threaten our people," he said.
As well as around 200 air strikes launched with Arab allies on Tuesday morning against IS, the US, on its own, launched around 20 Tomahawk cruise missiles against eight Khorasan Group targets near Aleppo in the north west of the country.
These targetted “training camps, an explosives and munitions production facility, a communications building and command and control facilities,” the Pentagon said.
US Attorney General Eric Holder told Yahoo News: "We hit them last night out of a concern that they were getting close to an execution date of some of the plans that we have seen.
"And the hitting that we did last night, I think, will probably continue until we are at a stage where we think we have degraded their ability to get at our allies or to the homeland."
Kuwaiti Muhsin al Fadhli, a long-term Al Qaeda member, is the leader of the group.
He has been tracked by intelligence services for nearly a decade.
In 2012, the US State Department put up a $7 million reward for information that led to the capture of the "senior facilitator and financier" who was, it said, based in Iran at the time.