According to recent sources, the number of dead humans amount to 250, yet that number will probably rise in the days to come. The BBC have a chronological timeline on the event, how it unfurled. They also report on "restrained coverage".
Either Russian authorities have no negotiating powers, or the hostage-takers went insane. Hopefully, if smoke clears regarding this incident, I hope Russian authorities are not to blame, as when they killed more civilians than hostage-takers a couple of years ago, at the siege of a Moscow theatre.