Baton Rouge police shooter signals 'horrendous acts of violence' in manifesto

Baton Rouge police shooter signals 'horrendous acts of violence' in manifesto

The man who ambushed and killed three law enforcement officers in Louisiana purportedly described his actions as a "necessary evil" in a self-described, handwritten manifesto that an Ohio man says was emailed to him by the gunman less than an hour before the shootings.