The Russian president's critics condemned the court proceeding that yielded the two-year prison sentences on Friday as part of a clampdown on a protest movement and reminiscent of show trials of dissidents in the Soviet era.

Police said on Monday they were searching for other members of the group over the February protest at Moscow's Christ the Saviour Cathedral, but had not yet identified the suspects.

They did not say how many people they were looking for, nor whether they faced arrest and charges. Five members of the anonymous feminist punk group stormed the church altar in brightly colored balaclavas, mismatched dresses and wielding an electric guitar, but only three were arrested and tried.

Although the search was launched before Friday's verdict, the determination of police to pursue other Pussy Riot members suggested the Kremlin would keep the heat on the band despite the furor over the punishment imposed on the three young women.

A lawyer for Pussy Riot, Mark Feigin, said he believed police knew the identity of the other two women and had video surveillance footage of them walking into the church.

He said the search handed police a tool to put pressure on any of Pussy Riot's 10 plus members continuing its protest. "If you put some unidentified persons on the wanted list, then you can arrest whoever you want in a balaclava," he said.

In an interview last week, other members of Pussy Riot - their faces hidden behind colorful masks like those worn during the "punk prayer" - said the trial had only strengthened their resolve to stage new protests.

On Friday, the band released a new song entitled "Putin is Lighting the Fires of Revolution."

Nadezhda Tolokonnikova, 22, Maria Alyokhina, 24, and Yekaterina Samutsevich, 30, were convicted of hooliganism motivated by religious hatred over their performance of a "punk prayer" urging the Virgin Mary to rid Russia of Putin.

A police spokeswoman said other unidentified members of Pussy Riot were being sought under a criminal case that was now separate from that against the three performers who were tried.

NO OFFENCE TO DEVOUT, PROTESTERS SAY

Tolokonnikova's husband, Pyotr Verzilov, said Pussy Riot members remaining at large want "normal lives" and painted the police statement as part of a wider Kremlin crackdown on opponents who hope to stage mass street protests in the autumn.

"Putin likes the taste of repression," he told Reuters.

Tolokonnikova, Alyokhina and Samutsevich said they had sought to protest against Putin's close ties with the Russian Orthodox Church and had not set out to offend believers.

Slovenian philosopher Slavoj Zizek, whose works are being read by Samutsevich in jail, said the trial showed Russia's system of power was "immensely fragile" and likened Pussy Riot to dissident poets in the era of Soviet dictator Josef Stalin.

"The greatest appreciation for poetry in Stalinism was that you could have been shot for a poem," Zizek said in Moscow.

The United States, European Union and several nations have called the sentences disproportionate, and Washington has urged Russian authorities to "review" the case.

Russian Foreign Minister Sergei Lavrov, asked about the Western criticism, warned against interference in judicial affairs and said people should not "go into hysterics" about the case. He denied accusations that the trial was politically motivated and said the women could still appeal.

"Let's not draw hasty conclusions or go into hysterics."

Putin himself, an ex-KGB spy who returned to the presidency for a third term on May 7 after a four-year spell as prime minister, said before the sentences were pronounced that the women did "nothing good" but should not be judged too harshly.

They have already been in jail for about five months, meaning they will serve another 19 but could be freed if Putin were to pardon them. The Orthodox Church signalled it would accept such a move by appealing, belatedly, for mercy.

Madonna denounced on Saturday the jail terms imposed on the three women. She said they were being sent to a "penal colony for ... a 40-second performance extolling their political opinions".

(Writing by Steve Gutterman and Alissa de Carbonnel, editing by Timothy Heritage and Mark Heinrich)

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