Four U.S. service members are dead after a refueling aircraft went down in Iraq, U.S. Central Command said on Friday.

"At approximately 2 pm ET on March 12, a U.S. KC-135 refueling aircraft went down in western Iraq. Four of six crew members on board the aircraft have been confirmed deceased as rescue efforts continue," CENTCOM posted on X.

"The circumstances of the incident are under investigation. However, the loss of the aircraft was not due to hostile fire or friendly fire. The identities of the service members are being withheld until 24 hours after next of kin have been notified."

CENTCOM said on Thursday in its initial report on the crash: "The incident occurred in friendly airspace during Operation Epic Fury, and rescue efforts are ongoing. Two aircraft were involved in the incident. One of the aircraft went down in western Iraq, and the second landed safely."