Felipe Calderon, the president of Mexico, has asked the US for "firm" measures against weapons trafficking, following the deaths of 15 people in drug violence in the country's border areas with the US since Sunday. The victims included five women and four boys less than 17-years-old, local officials said on Monday. Rival drug cartels are fighting increasingly bloody battles in the region to control narcotic trafficking to the US. The boys were shot and killed in Ciudad Juarez, Mexico's most violent city, situated across the border from El Paso in Texas. Among those killed was a local official in Ejido...