Two U.S. service members were killed in action on Friday in an Iranian ballistic missile and drone attack on U.S. and partner forces in Jordan, U.S. Central Command announced.

A third U.S. service member is missing, the command release added, while four more troops had to be medically evacuated to hospitals in Jordan.

Those four service members have since been discharged, the command added.

“Other personnel who were evaluated for minor injuries have returned to duty,” the release stated.

U.S. Central Command is withholding the identities of the dead until 24 hours after the service members’ next of kin have been notified.

Additional information about the attack had not been provided as of publication.