The Department has not included service members who died in Iran last weekend in their official list of casualties, according to a report.

"Every second Trump prolongs his war in Iran is another second our service members remain in danger," said one Democratic lawmaker, amid mounting concern over the human toll.

The Pentagon said Tuesday night that a U.S. soldier reported missing following Friday's attack on a base in Jordan is believed to be dead.

Eighteen U.S. soldiers have been killed in strikes so far.