On Sunday, a procession of thousands marched to the Moscow bridge where prominent Russian opposition figure Boris Nemtsov was gunned down. Waving Russian flags and holding posters of the slain Kremlin critic, the mourners made their way through the capital streets while under the watch of a heavy police presence.
The killing of Nemtsov on Friday, said to be the most notable assassination of a Russian political figure while Vladimir Putin has been in power, is a chilling moment for the nation's politics. Though Sunday's demonstrators carried signs reading "I am not afraid," a noted fear has reportedly swept through opposition figures since the killing as accusations swirl over who is responsible.
Putin has vowed to find the assassins, while others point out that just weeks before his death, Nemtsov said he worried the Russian president would have him killed.
Here are some of the most striking photos and video from the tens of thousands who marched in Moscow: