During the horrific attacks in Paris, Facebook Inc. made a tool available for people in the area to let friends know they were safe. Safety Check had never been enacted for something that wasn't a natural disaster, and as the death toll rose Friday, the company garnered praise for acting fast.

A few hours later, some users reacted differently: Where was Safety Check after suicide bombings in Beirut killed more than 40 people? Or after an attack at Garissa University College in Kenya left 147 dead?

Facebook Chief Executive Officer Mark Zuckerberg says critics were right. The social network will now activate Safety Check for a broader range of human disasters.