Mexico City's top prosecutor says kidnappers have killed a 5-year-old boy by injecting him with acid after his family sought police help, the Associated Press reported.
Attorney General Miguel Mancera says assailants injected acid into the boy's heart and buried him on a hill outside the capital.
Mancera's office says in a statement that the boy was abducted Oct. 26 from a street market in a poor neighborhood and was killed three days later.
Police say a taxi driver unknowingly drove a kidnapper and the child from the market to a house. The driver later saw the boy on a TV announcement seeking information and returned to the market to alert the boy's parents.
Five suspected kidnapers have been arrested. Mancera confirmed the killing Monday.