Authorities located four new mass graves in northern Mexico over the weekend after the arrest of a suspect in the kidnapping and killings of bus passengers, the Mexican military said.Sixteen bodies were discovered in the clandestine graves in San Fernando, in the state of Tamaulipas, which borders Texas. The most recent find brings to 88 the total number of bodies recovered from mass graves in the area.The military announced Sunday that it had captured Armando Cesar Morales Uscanga the day before in San Fernando.The suspect admitted his participation in the kidnapping and killings of bus passengers on two separate days in March, the military said.Morales provided information that led to the discovery of the other four graves, the military said.Along with his arrest, the military seized an...