A British man accused of being part of an Islamic State (IS) kidnap-and-murder cell known as the "Beatles" has been charged with terrorism offences after returning to the UK, police said on Thursday.
"A 38-year-old man has been charged with various terrorism offences following an investigation by the Met's Counter Terrorism Command," police said in a statement.
The Metropolitan Police, which leads anti-terror investigations in the UK, officially named the man as Aine Davis and said he has been remanded in police custody.
They said they arrested Davis after he landed at Luton airport on a flight from Turkey.
The suspect, who does not have a fixed address, was set to appear at Westminster Magistrates' Court in central London on Thursday morning.
A spokesperson for the Crown Prosecution Service (CPS) said it authorised police to charge Davis over alleged offences including "possession of a firearm for a purpose connected with terrorism".
He was allegedly a member of the IS cell that held dozens of foreign hostages in Syria between 2012 and 2015 and was known to their captives as the "Beatles" because of their British accents.
Davis converted to Islam and adopted the name Hamza, the CPS said in a statement. It said he had been deported to the UK by Turkish authorities.
The four members of the "Beatles" are accused of abducting at least 27 journalists and relief workers from the United States, Britain, Europe, New Zealand, Russia and Japan.
Two have already been brought to justice and one was killed.
They were all allegedly involved in the murders of American journalists James Foley and Steven Sotloff, as well as aid workers Peter Kassig and Kayla Mueller.
The quartet allegedly tortured and killed the four American victims, including by beheading, and IS released videos of the murders for propaganda purposes. (AFP)