Updated

A black Army veteran upset about fatal police shootings of black men and bent on exterminating white police officers killed five lawmen in a sniper attack that layered new anxiety onto a nation already divided about guns and how police treat African-Americans.

Micah Johnson, who donned a protective vest and used a military-style semi-automatic rifle, was killed by a robot-delivered bomb after the Thursday evening shootings, authorities said. It marked the deadliest day for U.S. law enforcement since the Sept. 11, 2001, terrorist attacks.

In all, 12 officers were shot just a few blocks from where President John F. Kennedy was slain in 1963.