MOSCOW—Russia’s most prominent opposition leader Alexei Navalny collapsed and died on Friday after a walk at the “Polar Wolf” Arctic penal colony where he was serving a long jail term, the Russian prison service said.
Mr. Navalny, a 47-year-old former lawyer, rose to prominence more than a decade ago with blogs on what he said was vast corruption and opulence among the “crooks and thieves” of Russia’s elite.





