MEXICO CITY — His voice cracking with emotion, President Felipe Calderon said Friday that the United States bore some blame for "an act of terror" by gangsters who doused a casino with gasoline and set a blaze that killed at least 52 people.
The attack Thursday in Monterrey, an industrial city of 4 million barely a two-hour drive from Texas, stunned Mexicans and seemed likely to mark a watershed in the country's intensifying war against criminal syndicates.
In a 20-minute televised address to the nation, Calderon gave an unusually blunt assessment of the causes of Mexico's surging violence before flying to Monterrey to place a wreath at the burned-out hulk of the Casino Royale.
He referred repeatedly to the attack as a terrorist act, elevating the conflict to a new level, at least linguistically, and casting it in terms of a broader struggle for control of Mexico. He said rampant corruption within his nation's judiciary and law enforcement bore some blame.
But in unprecedented, direct criticism of the United States, Calderon said lax U.S. gun laws and high demand for drugs stoked his nation's violence. He appealed to U.S. citizens "to reflect on the tragedy that we are living through in Mexico."
"We are neighbors, allies and friends. But you, too, are responsible. This is my message," Calderon said.
He called on the United States to "once and for all stop the criminal sale of high-powered weapons and assault rifles to criminals that operate in Mexico."
Calderon declared three days of national mourning.
The motive of Thursday's attack wasn't clear, but authorities indicated that it might have been part of an extortion campaign against one of many casinos that operate in Mexico on the margins of the law.
Calderon's blast at the United States underscored frustrations here that there's little appreciation north of the border for the role Americans have played in strengthening the cartels that are responsible for the grisly violence that's claimed as many as 40,000 lives in the last five years.
With weapons bought in the United States, the gangs, whose roots lie in drug smuggling but which have branched out into a variety of criminal enterprises, are better armed than the police tasked with combating them.
"Part of the tragedy that we Mexicans are living through has to do with the fact that we are next to the world's greatest drug consumer," Calderon said in his speech, "and also the greatest global arms vendor that pays billions of dollars each year to criminals."