British Islamic State militants known as The Beatles were on Wednesday indicted in the US over the kidnapping and killing of Western hostages, paving the way for the most high-profile terrorism trial in recent history.
Alexanda Kotey and El Shafee Elsheikh, from London, who are accused of being complicit in the murders of 27 people, were formally charged by the US Department of Justice with counts of conspiracy to commit homicide, hostage-taking resulting in death, and kidnapping resulting in homicide.
The pair arrived in Washington DC from al-Asad air base in Iraq on Wednesday, where they have been held in US custody for the past year.
Kotey, 36, and ElSheikh, 32, who have had their British citizenship revoked by the Home Office, will be prosecuted in a federal court in Alexandria, Virginia, which handles major national security cases.
The charges implicated the men in the capture and killing of the four American victims of the four-man cell of jihadists.
Announcing the charges during a press conference in the US, John Demers, assistant attorney general for National Security, said: "Today is a good day, but it is also a solemn one, today we remember the four innocent Americans whose lives were taken.
"We cannot bring back your children, but we will do all we can to achieve justice for you," he said, addressing the victims' families.
“If you have American blood in your veins, or American blood on your hands, you will face American justice.”
They are alleged to have detained or killed Western hostages in Syria between 2014 and 2015, including American journalists James Foley and Steven Sotloff and aid workers Kayla Mueller and Peter Kassig. The fourth member of the group is Aine Davis, who is in prison in Turkey.
Former hostages accused the men of regularly subjecting them to beatings during their time held in a prison run by Islamic State jihadists in the Syrian city of Raqqa, as well as waterboarding and mock executions.
In interviews while in detention in Syria, the two men admitted they helped collect email addresses from Ms Mueller, who was killed in 2015 after 18 months in IS captivity, that could be used to send out ransom demands.
The men's arrival in the US sets the stage for arguably the most sensational terrorism trial since the 2014 criminal case against the suspected ringleader of a deadly attack on the diplomatic compound in Benghazi, Libya.
"It was determined by courts that it was legal for us to provide further info to the US authorities," a spokesman for Boris Johnson, Prime Minister, said Wednesday. "We want justice to be done in this case."The move had been held up by disagreements between the US and the UK as to whether the latter would allow the men to stand trial in the US over objection over the death penalty."
The mother of ElSheikh had sought to block a US prosecution because of the prospect of execution if convicted. She lost her appeal at the High Court after Bill Barr, US Attorney General, gave assurances that he would not seek the death penalty for the men.
Last month the UK handed over vital evidence on Kotey and ElSheikh, which is thought to include intercepted communications, interviews with victims and witness testimony.
Should the men be found guilty in court, they could face life sentences in the notorious “supermax” prison, formally known as the US Penitentiary Administrative Maximum Facility, in Florence, Colorado.
The families of the victims welcomed the move, saying it was the start of a long road to justice.
“James, Peter, Kayla and Steven were kidnapped, tortured, beaten, starved, and murdered by members of the Islamic State in Syria,” said the James Foley Foundation is a statement. “Now our families can pursue accountability for these crimes against our children in a US court.
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“Kotey and ElSheikh's extradition and trial in the United States will be the first step in the pursuit of justice for the alleged horrific human rights crimes against these four young Americans, who saw the suffering of the Syrian people and wanted to help, whether by providing humanitarian aid or by telling the world about the evolving Syrian crisis.”
As well as the foreign hostages, Islamic State abducted hundreds of Syrians whose fate is still unknown.
Maisa Saleh, whose sister was captured by the jihadists in August 2013, said that she hoped any future trial would provide answers.
“The US trials are an opportunity to discover any information about the prisons, the transfer of the kidnapped, mass graves and their fate. Our eyes are on these trials hoping they will expose any detail related to our loved ones,” she said.
“We also ask the US government to interrogate the fighters who are captured by the SDF in the northeast. These fighters are banks of information that could be providing us with leads about our loved ones."