Two police offers were shot in a pizza restaurant in Las Vegas during a shooting spree that left at least three dead.
According to the Associated Press news agency, police said two suspects shot two officers who were eating lunch, with one shouting: "This is a revolution."
They were then said to have fled to Walmart across the street, where they shot a person before killing themselves.
The condition of the officers is not immediately known, the police spokesman said.
More top news
Emergency services have declared a "major incident" in Leicester following reports of an explosion.
Parts of the UK will feel colder than the Arctic Circle in the coming week as bitter winds make it feel -15C in some places.