An undocumented immigrant referenced by President Donald Trump in support of building a wall on the southern US border has been charged with killing four people in Nevada this month, prosecutors said Monday. Wilber Ernesto Martinez-Guzman, an El Salvadoran native who was arrested on January 19, admitted to killing a Reno, Nevada, couple using a gun he stole from their home, police said in a probable cause statement. He was not charged in the deaths at the time of his arrest. Authorities in Washoe and Douglas counties filed a criminal complaint charging Martinez-Guzman with four counts of murder, with the...