Russian President Vladimir Putin has visited the scene of a fire in a shopping mall in the Siberian city of Kemerovo. The fire killed at least 64, including as many as 41 children. Investigators said the mall's fire exits had been illegally blocked, and the fire alarm system hadn't functioned properly. Putin blamed the mall fire on "criminal negligence". Four people have already been detained over the incident. Rescuers were struggling to recover bodies. It's unclear whether any people remain unaccounted for.