The first US service members to die in the conflict between the US and Iran were killed by a direct Iranian strike on a makeshift operations center at a civilian port in Kuwait on Sunday morning local time, a source familiar with the situation told CNN.

The death toll from that attack at the Shuaiba port has since risen to six, US Central Command announced on Monday afternoon, after the remains of two additional service members were recovered.

Earlier Monday, Defense Secretary Pete Hegseth said that the strike that killed the service members hit a “tactical operation center that was fortified,” but there was “one” projectile that made it through air defenses. CNN previously reported the event was a suspected drone strike.

The source familiar said it was a direct hit just after 9 a.m. local time, on the center of the building they described as a triple-wide trailer with office space inside. The attack came quickly and with no warning or sirens to alert troops to evacuate or get into a bunker, the source said. Hours after the strike, fire was still smoldering in some parts of the building, the source described – the inside of the makeshift operations center blackened and the walls blown outwards from the blast, some parts peeling away from the building.

A satellite image taken Sunday morning showed a building at the port on fire and dark smoke billowing into the sky.

US Central Command initially said that three service members were killed but didn’t specify the location of the strike. There were dozens of people at the site, the source said, but the final service members who were declared killed in action were unaccounted for when the dust settled. With the building still burning in some places, it took time to recover the remaining service members, the source said.

The CENTCOM release on Monday also said a facility was struck “during Iran’s initial attacks.” The military has not identified the troops killed on Sunday, as families are still being notified.

CENTCOM’s statement said US forces “recently recovered the remains of two previously unaccounted for service members” from the facility that was struck.

The soldiers were assigned to 1st Theater Sustainment Command, a standalone headquarters based out of Fort Knox, Kentucky, with troops from other home units assigned to support in nine-month rotations.

The six casualties are the first killed in action in the military operation against Iran that began early Saturday Eastern standard time, dubbed Operation Epic Fury. Hegseth and President Donald Trump have both said that more casualties are likely. A CENTCOM spokesperson said Monday that 18 troops have been seriously wounded throughout the US military’s operation.

Speaking to reporters on Monday, Chairman of the Joint Chiefs of Staff Gen. Dan Caine called the service members killed in action “the best that our nation has to offer” and “true examples of what selfless service means.”

“Our deepest and heartfelt condolences are with their families, their friends, and their units,” he said. “We grieve with you and we will never forget you.” (CNN, excluding headline)

•PHOTO: The above pairing of images shows the location where American service members were killed in Kuwait. The left images was taken on June 26, 2025. The image on the right was taken on March 1, 2026. (Planet Labs PBC via CNN)

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