Did a Mexican political party have agreements with organized crime?

Did a Mexican political party have agreements with organized crime, specifically the PRI which governed Mexico for 71 years?
The way Mexican President Felipe Calderon answered this question when asked by New York Times reporters is creating quite a stir. Asked whether he fears that a victory by the PRI in next year's presidential elections may bring back a corrupt relationship with organized crime, Calderon, a member of the PAN, conceded that is one of his fears.