US takes custody of notorious British IS 'Beatles' from Kurdish forces

Two British militants thought to be part of an Islamic State group dubbed "The Beatles" that allegedly beheaded hostages have been moved out of a detention centre in Syria and are now in US custody.

The pair, El Shafee Elsheikh and Alexanda Amon Kotey, were part of an extremely violent all-British four-man cell that kidnapped and tortured foreigners, including journalists, at the height of the Islamic State group's power in Syria and Iraq.

"In case the Kurds or Turkey lose control, the United States has already taken the 2 ISIS militants tied to beheadings in Syria, known as the Beetles, out of that country and into a secure location controlled by the US," President Donald Trump tweeted.

"They are the worst of the worst!"

A US defence official had earlier confirmed they had taken custody of two "high-value" IS individuals from the Kurdish-led Syrian Democratic Forces (SDF) that held the captured militants.

"They have been moved out of Syria and are in a secure location," the official said, without identifying where. "They are being held in military custody pursuant to the law of war."

Read more: What happens next? Turkey launches a new offensive in Syria

One other member of the four-man militant cell was killed in a drone strike and the fourth is imprisoned on terror charges in Turkey.

Turkey has launched an assault on the Syrian Kurdish forces - with which the US partnered to combat IS militants - sparking fears that the offensive could lead to captured fighters they held escaping and reconstituting the group.

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'Particularly bad'

The cell of the two militants is accused of abducting and decapitating around 20 hostages including American journalist James Foley, who was beheaded in 2014.

Trump had earlier said the US was taking steps to prevent the potential escape of particularly dangerous Islamic State group fighters amid the Turkish offensive.

"We are taking some of the most dangerous ISIS fighters out and we're putting them in different locations where it's secure," Trump said at the White House.

"We have taken a certain number of ISIS fighters who are particularly bad and we've wanted to make sure nothing happened to them with respect to getting out," he said.

The move addressed one of the most worrisome issues of Trump's green light to Turkey to invade Syria, where the Kurds, a long-time US battlefield partner, are viewed as a terror threat by Ankara, a NATO ally of Washington. 

The SDF have been holding prisoner some 10,000 captured Islamic State group fighters.

The SDF-held fighters include around 2,000 of foreign nationality, many of them from European countries that have refused to take them back.

Trump said the Kurds were still guarding many of the Islamic State group militants, but also said Turkey would be responsible for them.

"If the Kurds don't watch, Turkey will watch. They don't want those people out any more than we do," he said.

Agencies contributed to this report.

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