RFE/RL Russian Service correspondent Oleg Kusov said that protesters were greeted with a strong police presence.
"After every 10 meters there was a column of policemen. They were in plainclothes, but nevertheless, they had a psychological influence. Next to the policemen there were trucks with water cannons.... The organizers aren't giving any cause for the police to use force. And I think the intensity of passions is diminishing," Kusov said.
Kusov estimated that there were no more than 200 marchers present. He said some local journalists said they recognized members of the security services in the crowd.
Protesters marched with slogans such as "We want a different Russia," and "Russia without Putin and his disciples."
The rally was officially sanctioned, but it follows a week of crackdowns against activists in Samara and elsewhere.
Law-enforcement officials seized computers at the Samara office of the liberal weekly "Novaya gazeta" last week. Police reportedly said they were searching for pirated software.
Police also raided the Samara branch of Voice, a rights group that has actively denounced arrests of opposition activists.
Some of the activists, traveling from other parts of Russia, didn't make it to Samara. Former chess champion Garry Kasparov, now a leading figure in the Other Russia opposition movement, was detained this morning at Moscow's Sheremetyevo Airport as he was attempting to board a plane to Samara.
Officials have claimed Kasparov's ticket was improperly issued. Several Western journalists and other opposition figures were also barred from boarding the plane.
Speaking to RFE/RL's Russian Service, Kasparov said he was not allowed to fly out of Moscow.
"Most [of the group members] had their passports and tickets taken away. This continued for almost five hours and there was no explanation given for the first two hours. After that they said they were gathering information about the tickets because supposedly 13 passengers [from the group] -- including correspondents from 'The Wall Street Journal' and 'The Daily Telegraph,' by the way -- had forged tickets," Kasparov said.
Eduard Limonov, whose barred National Bolshevik Party is also a member of Other Russia, was among those detained.
He told RFE/RL's Russian Service he believes the confrontation with authorities indicates the opposition is stronger than the Kremlin would like.
"The polarization between the Kremlin and the Other Russia [movement] continues, and as far as I understand it is becoming public knowledge among Russian citizens despite the silence of federal television stations and the federal media. As far as I'm concerned, I'm glad it's happening. I think this is the kind of conflict that opposition activities have been missing for many years," Limonov said.
Requests to hold such marches in other Russian cities are often rejected, and attempts to defy the bans have met with a brutal police crackdown.
In Samara, German Chancellor Angela Merkel told journalists she was "concerned" by the fact that activists had had difficulty traveling to the city.
"I say this openly that I wish that this afternoon, those who want to demonstrate in Samara and express their opinion will be able to do so. I am a little concerned that a number of [people] had difficulty in traveling here, but perhaps they will be able to accomplish this, nevertheless," Merkel said.
Putin appeared unfazed by any critical voices. He said the March of Dissent opposition rallies -- which have been staged in Moscow, St. Petersburg, and Nizhny Novgorod -- "pose no problems" to him.
"We shouldn't be afraid of marginal groups, especially such small groups. Practically in all countries law enforcement agencies take preventive measures. Is it good or bad? I think sometimes it's not always justified. And such examples have been cited today. There are such examples in Germany too, where they arrest and detain people as a preventive measure," Putin said.
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