According to witnesses, the 48-year-old man and his wife got on the bus near R. Michel and Calzada Independencia in the city center. The assailant, who got on at the same stop, waited more than 15 minutes before making his move.
When confronted by the gunman, the victim refused to hand over the package containing the jewels and received a blow to the head, causing him to drop to the floor of the bus. The gunman then shot him in the head at point-blank range before fleeing the bus without the package. Witnesses said he got into a car that pulled up beside the bus.
The bus driver immediately drove the injured man to a nearby medical clinic but doctors there were unable to save him.
Authorities say the number of incidents of criminals targeting people who have just left banks (or in this case a pawn shop) after making withdrawals has risen substantially in recent years.