World news: Three US police men killed by an unknown gun man

Authorities in the American state of Louisiana said a masked man has shot three policemen in Baton Rouge, less than two weeks an African-American man was allegedly killed by policemen in the same town.

The extent of the officers’ injuries is not known. But CNN reported that the officers might have been killed.

Five police officers were killed and seven others wounded by a sniper during a protest against police shootings of black men on July 8 in Dallas, Texas.The suspect, 25-year old Micah Johnson, was later killed by a bomb-carrying robot used by Dallas police department. The identity of the latest shooter and his motive are not known yet.