Muoz had headed a chemical and petrochemical workers union for about four decades. He also had been a federal senator for the then-ruling Institutional Revolutionary Party and had served several terms in the federal congress. He also was a senior official in the main country's main labor federation, the Mexican Confederation of Workers.
The motive for the slaying wasn't immediately clear.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)