MOSCOW — Two Russian opposition leaders were questioned by investigators Wednesday, a day after they helped organize the largest protest against Vladimir Putin since his return to the presidency in May. Anti-corruption whistleblower Alexei Navalny and leftist leader Sergei Udaltsov were questioned as part of an investigation into an earlier rally on May 6 that ended in fierce clashes. But they were summoned for interrogation and had their apartments raided on the eve of Tuesday’s rally in what was seen as part of Kremlin efforts to discourage people from attending the anti-Putin protests. — AP