The White House on Wednesday expressed concern about a violent crackdown on anti-government protesters in Iran as President Barack Obama said he wanted the U.S. and Iran to move beyond "suspicion, mistrust and confrontation."

Iranian security forces clubbed anti-government protesters with batons on the sidelines of state-sanctioned rallies to mark the 30th anniversary of the U.S. Embassy takeover. The counter-demonstrations were the opposition's first major show of force on Tehran's streets in nearly two months.

"We obviously have seen and are following the reports of this, and hope greatly that violence will not spread," White House spokesman Robert Gibbs said.

Witnesses told The Associated Press that security forces swept through a gathering of hundreds of demonstrators by clubbing, kicking and slapping protesters.

The unrest came 30 years after militant Islamic students stormed the embassy in Tehran. With support from the Iranian government, 52 Americans were held hostage for 444 days.

The crisis "deeply affected the lives of courageous Americans who were unjustly held hostage, and we owe these Americans and their families our gratitude for their extraordinary service and sacrifice," Obama said in a statement issued late Tuesday.

"This event helped set the United States and Iran on a path of sustained suspicion, mistrust and confrontation," Obama added. "I have made it clear that the United States of America wants to move beyond this past, and seeks a relationship with the Islamic Republic of Iran based upon mutual interests and mutual respect. ... We have made clear that if Iran lives up to the obligations that every nation has, it will have a path to a more prosperous and productive relationship with the international community."

After Obama's statement, Mohamed ElBaradei, director general of the International Atomic Energy Agency, the U.N. nuclear watchdog, said he believes the U.S. and Iran are at a turning point in relations that could produce a productive dialogue between the two nations.

Speaking to the Council on Foreign Relations in New York, ElBaradei cited Obama's willingness to seek a relationship with Iran and the recent face-to-face talks between the two countries on the sidelines of discussions about Tehran's nuclear program _ the first direct talks since the 1980 embassy takeover.

ElBaradei called these "little steps that could lead to huge results" but warned that "it's a unique opportunity, but it's also a fleeting opportunity." Continued...