About 7,500 people took to the streets of Moscow Saturday in a rally on the first anniversary of the assassination of Russian opposition leader Boris Nemtsov, according to official figures reported by the Interior Ministry.
The opposition-oriented news agency Dozhd reported that the turnout might have been closer to 20,000.
The rally was one of more than a dozen in major Russian cities honouring Nemtsov, a former deputy prime minister who became a fiercely outspoken critic of longtime President Vladimir Putin.
The march drew strong support from Nemtsov's political party, the People's Freedom Party, commonly known by its Russian acronym PARNAS.
Mikhail Kasyanov, a former prime minister under Putin, marched at the front of the crowd. Kasyanov is running for election to the federal parliament this year as a leader of PARNAS.
"We will never forget and never forgive," the demonstrators chanted.
"I'm here to commemorate a great man who dreamed of a democratic Russia," a Muscovite told dpa. "I was completely shocked when I heard the news one year ago."
The march was officially allowed to take place in a northern part of central Moscow, relatively far from the bridge outside the Kremlin where Nemtsov was shot while walking home at night with a female companion from Ukraine last year.
Rallies in Moscow are illegal if not specifically permitted by the authorities, so there was a potential for a police crackdown if the marchers headed to the bridge.
Open Russia, a pro-democracy organization run by self-exiled opposition leader Mikhail Khodorkovsky, said they would lay flowers on the bridge at night to mark exactly one year since Nemtsov was shot.
Nemtsov's murder occurred days before he was expected to lead a major opposition march and release a controversial report about alleged Russian military involvement in the Ukraine conflict. Open Russia later released the report.
In December, Russia's federal Investigative Committee said it was indicting five men in the suspected contract killing.
The alleged triggerman, Zaur Dadayev, was previously a soldier in southern Russia's predominantly Muslim region of Chechnya.
Dadayev confessed early in the investigation to killing Nemtsov for insulting Chechnya's leader, Ramzan Kadyrov, as well as Islam, according to Russian media reports citing investigators at the time.