The State Department Thursday urged restraint by Iranian authorities after reports Tehran police beat demonstrators calling for the release of imprisoned journalist Akbar Ganji. The Ganji case has drawn top-level U.S. attention.

The Bush administration is continuing its criticism of Iran's handling of the Ganji case, amid reports authorities used force to break up a protest by supporters of the jailed journalist late Tuesday in Tehran.

An investigative reporter for a Tehran newspaper and critic of Iran's clerical leadership, Mr. Ganji was sentenced to six years in prison in 2001 following a series of articles he wrote linking senior officials to the killing of political dissidents.

The United States has joined international human rights groups in taking up Mr. Ganji's cause in recent days, following statements by family members that he is in ill-health from a hunger strike he began more than a month ago.

The State Department called for Mr. Ganji's immediate and unconditional release late last month, saying he is imprisoned solely for his political views and peaceful activities.

In a written statement Tuesday, the White House repeated the call and said President Bush is saddened by reports of Mr. Ganji's failing health, and deeply concerned that he has been denied access to his family, medical treatment and legal representation.

Briefing reporters here Thursday, acting State Department Spokesman Thomas Casey reacted strongly to reports that a crowd of mainly student supporters of Mr. Ganji had been forcibly dispersed outside Tehran University. "We're disturbed by reports of police brutality against peaceful protesters who were demonstrating in Tehran on Tuesday to call attention to Mr. Ganji's case. And we call on the Iranian regime to exercise restraint, and to permit the Iranian people to exercise their legitimate right to peaceful assembly and to free speech," he said.

Family members and supporters of Mr. Ganji in Iran say he has lost more than 18-kilograms of weight in the hunger strike and that his life is in danger.

But Iranian judicial officials said Thursday he is under special medical care and not in failing health.

The Iranian government has also lashed out at U.S. intervention in the case, saying the Bush administration is in no position to lecture Iran given what it said are U.S. human rights violations at the Guantanamo Bay detention facility in Cuba and the Abu Ghraib prison in Iraq.

Under questioning here, Spokesman Casey rejected a comparison of the Ganji case and that of New York Times reporter Judy Miller, who has been sent to jail by a Washington judge for refusing to disclose news sources in an Iraq-related investigation of who exposed the identity of a CIA agent.

Mr. Casey said the United States' record on press freedoms compares favorably with that of any other country, and that the Miller case has not caused other governments to be dismissive of U.S. efforts on behalf of Mr. Ganji.

In its statement Tuesday, the White House said Mr. Ganji is sadly only one victim in a wave of repression and human rights violations by the Iranian government.