A medic escorts a woman to an ambulance after she left the Tasso da Silveira school where a gunman opened fire on children in the Realengo neighborhood of Rio de Janeiro April 7, 2011. A gunman killed 12 people in a shooting spree at the school before killing himself, police said on Thursday, an incident apparently unrelated to the city's ongoing gang violence. REUTERS/Ricardo Moraes (BRAZIL - Tags: CIVIL UNREST CRIME LAW)