Serbia held a national day of mourning Wednesday as police searched for possible motives in the Balkan nation's worst peacetime shooting massacre, which left 13 villagers dead and triggered demands for tighter gun-control laws. Police say a 60-year-old veteran went on a pre-dawn, house-to-house rampage Tuesday in a village near Belgrade, including killing his mother, his son and a two-year-old cousin before shooting himself and his wife. The two are in critical... (GunPolicy.org)