MOSCOW (AFP) — Russian police late Friday raided an office of The Other Russia coalition led by former chess champion Garry Kasparov, hours before he was to lead a march in Moscow against President Vladimir Putin.

The coalition's spokeswoman Lyudmila Mamina told AFP that the police did not proffer any explanations for the raid in the office housing the party's website.

"They had no documents, acted on the authority of some secret decree, so they could not say what it was about," she said.

"They wrote down passport data of all our staff, drew a map of the office, and wrote down that they found nothing criminal, no drugs, no weapons."

"It was all connected to (Saturday's) March of Dissenters. It was an attempt to scare off its organisers," said, adding: "Our staff reacted calmly. This is not the first such raid, a year ago they broke in with weapons ..."

The March of the Dissenters is due to be held in Moscow on Saturday morning. Kasparov, who intends to stand for the presidency, will lead the "Russia without Putin" march.

Leaders of Russia's liberal opposition party, the Union of Right Forces (SPS), on Friday nominated an architect of post-Soviet economic reform, Boris Nemtsov, as their presidential candidate.

The decision comes after President Vladimir Putin on Wednesday dubbed his political opponents Western-funded "jackals," amid an increasingly tense run-up to March's presidential poll.

About 200 activists from across Russia attended Friday's meeting of the SPS, which has signalled a determination to keep fighting despite abysmally low poll ratings and warnings of disunity in opposition ranks.

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