Clinton and other U.S. officials pointed to Mexican drug cartels' use of car bombs, a tool once favored by cartel-allied rebels in Colombia.
The Mexican government quickly condemned the killing of the mayor of the northern town of El Naranjo. But it rejected the comparison with Colombia, where the Medellin drug cartel waged a full frontal assault on the state.
Mexico also bristled at Clinton's suggestion that the U.S. was looking to implement some type of Plan Colombia for Mexico and Central America. She was referring to a U.S. anti-drug program in which American special forces teams trained Colombian troops and U.S. advisers are attached to Colombian military units.