RIO DE JANEIRO — Brazil, which has one of the world's highest murder rates, will hold a referendum on Sunday on whether to ban sales of guns to the public. More than 500,000 were killed in Brazil between 1979 and 2003, according to UN figures, and many tourists now think twice about a walk along Rio de Janeiro's famous Copacabana beach for fear of being held up at gunpoint. There are more than 17 million firearms in Brazil, of which nine million are not... (GunPolicy.org)