 Although violence between drug cartels had been occurring long before the war began, the government held a generally passive stance regarding cartel violence in the 1990s and early 2000s.That changed on December 11, 2006, when newly elected President Felipe Calderón sent 6,500 federal troops to the state of Michoacán to end drug violence there (Operation Michoacán).This action is regarded as the first major operation against organized crime, and became the starting point of the war between the government and the drug cartels.