The White House confirmed the death of U.S. aid worker Peter Kassig, according to The Associated Press.
The news came after militants released a video Sunday claiming Kassig had been killed. The video showed the aftermath of the beheading. Earlier reports could not identify the victim or confirm the death.
Kassig, 26, did aid work in Syria. Kassig had gone to the Middle East as a soldier and went back as a medical worker. Prior to the confirmation, the United States condemned the attack, according to CNN.
"If confirmed, we are appalled by the brutal murder of an innocent American aid worker and we express our deepest condolences to his family and friends," National Security Council spokeswoman Bernadette Meehan said according to CNN.
Kassig is the fifth Westerner that ISIS beheaded, according to CNN.