Thousands of people have marched in Moscow to honour opposition politician Boris Nemtsov, who was shot dead in the Russian capital on Friday night, BBC reports.
Mourners gathered at a point not far from the Kremlin before marching past the spot on Bolshoi Moskvoretsky Bridge where Nemtsov was killed. Some were carrying portraits of him and banners saying "I am not afraid".
Nemtsov's allies have accused the Kremlin of involvement and say it was a political killing linked to his opposition to President Vladimir Putin and Russia's involvement in the Ukraine conflict.
But Putin condemned the murder as "vile" and vowed to find the killers.
Police said 21,000 people attended the march. The organisers put the numbers at tens of thousands, but attendance appeared smaller than the 50,000 people the opposition had hoped for. Several thousand people also marched in St Petersburg.
The authorities have suggested the opposition itself may have been behind his shooting in an attempt to create a martyr and unite the fractured movement. His supporters have blamed the authorities.
The opposition leader's murder has divided opinion in a country where for years after the Soviet Union collapsed many yearned for the stability later brought by former KGB agent Vladimir Putin.
A small but active opposition now says Putin's rule has become an autocracy that flaunts international norms after Russia seized Ukraine's Crimea peninsula last year, fanned nationalism over the separatist war in eastern Ukraine and clamped down on dissent.