South Korean investigators combed footage on Monday from more than 50 state and private closed-circuit TV cameras as well as from social media looking for answers to how a surge in Halloween party-goers trapped in narrow alleys killed so many.
As the country began a week of mourning, the death toll climbed to 154. Another 149 people were injured, 33 of them in serious condition. Citizens from at least two dozen countries were among the dead.
