Two Americans are among the casualties in the devastating earthquake that rocked southeastern Iran, a State Department official said Saturday.

Spokesman Lou Fintor (search) said one American was killed and another was injured in Friday's powerful quake in the ancient city of Bam.

The State Department (search) did not release the names of the two Americans, who were visiting the city's 2,000-year-old citadel at the time.

Fintor said the injured American has been hospitalized in Tehran (search) and is receiving medical care. The injuries are serious but do not appear to be life-threatening, he said.

Iran's Interior Ministry has estimated that about 20,000 people were killed in the earthquake, but rescue officials said the number could be twice as high.

More than 30,000 people were injured.

In a statement of Friday, President Bush offered his condolences to "all those touched by this tragedy." The White House said the United States will provide humanitarian assistance to Iran, but did not offer specifics on what form the aid might take.