An Islamic State (IS) group suspect from the UK has pleaded guilty in a US court to charges of conspiring to murder four American hostages.
Kotey and fellow "Beatle" El Shafee Elsheikh initially pleaded not guilty at a hearing last October.
The change of plea suggests Kotey may co-operate with prosecutors, reports BBC.
Kotey, 36, and Elsheikh, 32, are on trial for their involvement in the murders of US journalists James Foley and Steven Sotloff, and relief workers Peter Kassig and Kayla Mueller.
They were flown from US custody in Iraq last year to face the charges, which carry a maximum penalty of life in prison.
There is no word yet on whether Mr Elsheikh has reached a plea deal with authorities.