The former head of Guatemala's police force and his 2-year-old grandson were slain by gunmen as they drove through the center of Guatemala City, police said. Retired Gen. Manuel Francisco Sosa Avila, 65, and his grandson, Roger Manuel Mungia, were shot several times in the chest and head. The general's daughter, who was also in the car, was slightly wounded. The killers escaped, and no one has claimed responsibility for the attack. Sosa Avila, brother-in-law of former President Efrain Rios Montt, headed Guatemala's police force from 1970 to 1974.