The Pentagon said on Monday that it was not aware of any Iranian deaths in the recent U.S. strikes against Iran-linked targets in Iraq and Syria.
The United States launched airstrikes in Iraq and Syria on Friday against more than 85 targets linked to Iran's Revolutionary Guard (IRGC) and militias it backs in retaliation for a deadly attack on U.S. troops.
Air Force Major General Patrick Ryder told reporters initial indications were that the strikes did not kill any Iranians. But he said other casualties other were likely, without giving details.
Iraq's Popular Mobilization Forces, a state security force including Iran-backed groups, said 16 of its members were killed including fighters and medics. The government earlier said civilians were among 16 dead.
In Syria, the strikes killed 23 people who had been guarding the targeted locations, said Rami Abdulrahman, director of the Syrian Observatory for Human Rights, which reports on war in Syria.
"It's fair to conclude that there likely were casualties associated with these strikes," Ryder told reporters, but said an assessment was ongoing.
He added that there had been two attacks against U.S. troops in Syria since the Friday strikes, but there were no U.S. injuries.
The Pentagon has said it does not want war with Iran and does not believe Tehran wants war either, even as Republican pressure has increased on U.S. President Joe Biden to deal a blow directly.
Reporting by Phil Stewart and Idrees Ali