Alejandra Maria Torres sits bloodied on a street after being beaten, doused with petrol and set on fire during a lynching in Guatemala City    Passengers of a public bus accused Torres and three men, who escaped on foot, of participating in an armed robbery   Stripped naked to the waist, she begs for mercy as she is savagely beaten by a lynch mob in the middle of the street.   Alejandra Maria Torres was part of an armed gang that tried to rob bus passengers in Guatemala City.   But as she tried to escape the passengers stripped and beat her before