WASHINGTON (AP) – The White House on Monday sharply criticized Russia’s harsh handling of anti-government demonstrators, saying it was part of “an emerging pattern of use of excessive force by the authorities.”

The criticism came after riot police beat and detained dozens of anti-Kremlin demonstrators Sunday in St. Petersburg on a second day of protests that tested the weak opposition’s ability to challenge widely popular President Vladimir Putin. On Saturday, police in Moscow forcefully broke up protests by an anti-government coalition led by former world chess champion Garry Kasparov.

“We are deeply disturbed by the heavy-handed manner in which this weekend’s demonstrations in Moscow and St. Petersburg were broken up by the authorities and by an emerging pattern of use by excessive force by the authorities in reaction to similar events,” White House spokeswoman Dana Perino said. “We also find it intolerable that journalists were detained, an unacceptable practice that hinders freedom of the press.

“We underscore that allowing peaceful expressions of protest is an element of democracy and a universally recognized human right,” Perino said.

She said she did not believe that President Bush had spoken with Mr. Putin about the incidents.

Ms. Perino said America supports calls for an investigation of the government’s actions. She urged the Kremlin to reiterate its commitment to respect international standards of freedom of speech, the media and the right of assembly.

Opinion polls rate Mr. Putin as Russia’s most popular political figure by far, thanks to newfound political stability and rapid economic growth fueled by high world oil prices. That popularity has cowed mainstream politicians in parliament and allowed Mr. Putin to strengthen the Kremlin’s powers.

Mr. Putin’s foes said the harsh handling of demonstrators, who included many elderly people, would fuel a growing sense that the leader is strangling democracy ahead of parliamentary elections in December and a presidential vote next spring.