Updated Saturday at 12:50 p.m. ET
A French police officer who was severely wounded on Friday after exchanging himself for a gunman's hostage has died of his injuries, raising the death toll in the attack to four, according to French Interior Minister Gerard Collomb.
Col. Arnaud Beltrame, 44, was one of the first police officers to respond to the attack on a supermarket in southern France, which began after a gunman killed one victim in a carjacking, then killed two others in the grocery store. Sixteen others were also wounded in the attack.