If the newly elected Iranian president turns out to have been a main participant in the holding of American hostages in Tehran, he won't be the first top Iranian official with a role in the 1979 crisis.

The current Iranian environment minister, Massoumeh Ebtekar (search), was the chief interpreter and spokeswoman for the radical students who took over the U.S. Embassy and held 52 Americans hostage for 444 days.

Dubbed "Sister Mary" by the American press because her heavy head scarf resembled a nun's habit, Ebtekar gave almost nightly interviews during the standoff, denouncing the hostages as spies and accusing the United States of committing crimes.

Five former U.S. hostages who saw Iranian president-elect Mahmoud Ahmadinejad (search) in photos or on television said they believe he was among the hostage-takers. One said he was interrogated by Ahmadinejad.

The White House said Thursday it was taking their statements seriously. President Bush said "many questions" were raised by the allegations of the former hostages. The State Department said it is investigating.

Some of the former students have said Ahmadinejad opposed the takeover and played no role in it, even though he was a member of the hard-line Islamic student group that seized the embassy.

Ebtekar, who is also one of Iran's six vice presidents, has been the highest-ranking woman in the moderate-leaning government of President Mohammad Khatami (search).

She acknowledged her part in the U.S. Embassy takeover in remarks to reporters in 1998.

"The generation that is in executive and policy-making jobs is a revolutionary generation that played an active role in every stage of the revolution," Ebtekar said then.

A report in The New York Times that year had detailed her involvement, which was not listed on Ebtekar's biography.

She was an 18-year-old freshman at Polytechnic University in Tehran when she became the public voice of the student takeover. She spoke English better than others in the student group because she had lived in suburban Philadelphia as a child and had attended American schools.

She once told an ABC News reporter that she could imagine being provoked into killing the hostages.

"Yes," she said. "When I've seen an American gun being lifted up and killing my brothers and sisters in the streets, of course."

In the turbulent early days of Iran's Islamic Revolution, Ahmadinejad was more concerned with putting down leftists and communists at universities than striking at Americans, former students said. During the long standoff, he was writing and speaking against leftist students, they said.

It is unclear whether the Bush administration had explored previously whether Ahmadinejad was involved in the hostage episode. National security adviser Stephen Hadley (search) said Thursday that the United States has followed his career.

"Obviously, one of the things you do when you get a report like this is look back and see what you have in the files and that's the process that's going on now," he said.

Hadley said the White House was looking into the photographs and had not reached any conclusions.

"They are allegations at the present time," he said. "We need to get the facts."

Hadley stressed that the United States would have to deal with Ahmadinejad, even if the administration did not approve of the way he was elected. Bush denounced the election, saying it was designed to maintain power in the hands of an unelected few who denied ballot access to more than 1,000 people who wanted to run.