See photos and videos from Russia’s massive mourner march

Carrying posters and banners saying “I’m not afraid,” tens of thousands of Russians marched through central Moscow Sunday to honor opposition leader Boris Nemtsov, gunned down near the Kremlin on Friday night.

Nemtsov had originally planned the event to protest President Vladimir Putin’s handling of the economy, but the rally transformed into a public mourning after his death.

See photos and videos from Moscow’s streets below.