Baton Rouge shooter was ex-Marine who denied ties to any group

Law enforcement vehicles block access to Airline Highway near the scene of a fatal shooting of police officers in Baton Rouge. REUTERS/Jonathan Bachman

Gunman kills three police officers in Louisiana; Obama condemns attack

Police officers block off a road after a shooting of police in Baton Rouge, Louisiana, U.S. July 17, 2016. Reuters/Joe Penney