32 militants took more than 1,200 people hostage at the school in 2004 . Militants demanded Russia withdraw from breakaway republic of Chechnya . The siege ended when Russian forces stormed the building and freed all hostages, but it left hundreds dead on both sides. Criticism remains about how government has handled investigation of attack .
32 militants took more than 1,200 people hostage at the school in 2004 . Militants demanded Russia withdraw from breakaway republic of Chechnya . 334 people -- including 180 children -- died during attempt to end siege . Criticism remains about how government has handled investigation of attack .