Gunman signals 'horrendous acts of violence' in manifesto

(AP) — 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.

Photographs of the three-page letter show it was signed by "Cosmo," the first name of an alias used by Baton Rouge gunman Gavin Long, and the pictures were attached to an email sent from a Google address Long used.

The violence capped two weeks of turmoil for Baton Rouge that began with the killing of a black man, Alton Sterling, during a scuffle with two white police officers at a convenience store.

Todd Lindgren, a spokesman for the FBI office in Cincinnati, said he could not respond to any questions about the case "due to the Baton Rouge matter being an ongoing investigation," and the FBI's New Orleans office also declined comment.

Louisiana State Police Col. Mike Edmonson said law enforcement officers found an array of handwritten documents in Long's car and a hotel where he was staying, but he did not know if the material included the letter Karama shared.

Karama, who described himself as a hip-hop artist and community activist, said he provided other information about Long's emails to various news outlets.