MOSCOW — Alexei Navalny, Russian President Vladimir Putin’s most formidable critic, was lowered into the bottom to the strains of Frank Sinatra’s “My Method” as hundreds of his supporters exterior the cemetery chanted to be allowed in to pay their respects. Underneath the supervision of busloads of riot police, Navalny’s physique was whisked into the church for a quick ceremony earlier than being taken for burial. The opposition chief died abruptly on the age of 47 within the Polar Wolf jail colony in northern Russia — a loss of life that his widow, Yulia Navalnaya, and different supporters have described as “homicide” however which Russian authorities attributed to “pure causes.”