Soldiers opened fire on a pickup truck that refused to stop at a roadblock in northern Mexico, killing two women and three children.
The Defense Department said it had no immediate information on the reported shooting Saturday in Sinaloa state, home to many the country's drug cartel leaders. Sinaloa state police did not immediately return calls seeking comment Sunday.
The daily newspaper Reforma quoted Sinaloa police as saying the victims were members of two families traveling to a funeral in a remote area near the Sinaloa-Chihuahua border.
Police identified the victims as Alicia Esparza Parra, 17; Griselda Galaviz Barraza, 25; and Galaviz Barraza's children, Joniel, 7; Griselda, 4; and Juana, 2, the newspaper said.