Crowd numbers
Wide variations in crowd numbers. The Russian Interior Ministry says 16.5 thousand so far. Organizers say between 50,000 and 100,000.
One thing's missing from today's march: Nemtsov himself.
The Russian Service of Deutsche Welle says more than 70,000.
Breaking:
Russian TASS news agency reporting that Russia's Investigative Committee is offering 3 million rubles for useful information about Nemtsov's murder.
Many of those mourning Nemtsov have blamed his death on Russian propaganda, led by Russian TV, which has relentlessly portrayed the opposition as a Western-backed fifth column out to weaken the country.
Massive crowds still trying to get through metal detectors. AFP estimates more than 10,000 people so far.