Freeze, flight or fight: what to do in a terror attack

How should one react when confronted by armed attackers? Many of those killed at the Bataclan concert hall in Paris were asked to lie down. They complied, but this made it easier to kill them. Dr James R. Alvarez is a hostage situation specialist who thinks that following gunmen's orders can sometimes be the wrong thing to do.

(Photo: Rescuers and police stand near the Bataclan concert hall in central Paris. Credit: Miguel Medina/AFP/Getty Images)