Russian artists residing in Buenos Aires started Sunday to paint a large portrait of the late Russian opposition leader Alexei Navalny but were stopped by local police shortly before finishing it. Dozens of supporters were present. Navalny, who crusaded against official corruption in Russia and staged massive anti-Kremlin protests as President Vladimir Putin’s fiercest foe, died on February 16 in the Arctic penal colony where he was serving a 19-year sentence. Officials said he died of natural causes. Before his arrest, Navalny campaigned against official corruption, organized major anti-Kremlin protests, and ran for public office.