MOSCOW - Police have killed a senior Islamist militant in Russia's North Caucasus ahead of the Winter Olympics in Sochi, where security forces searched on Tuesday for a woman they fear is planning an attack during the Games. Eldar Magatov, a suspect in attacks on Russian targets and alleged leader of an insurgent group in the Babyurt district of Dagestan, died in a shootout, the National Anti-Terror Committee said on Tuesday.