MONTERREY, Mexico (AP) - Mexicans have endured plenty of horrific crimes during their country's bloody five-year war against drug gangs: bodies hanging from overpasses, beheadings, mass slayings of migrants and gunfights on crowded steets.
The torching of the casino that killed at least 52 people on Thursday, however, was a shocking new low for many.
In a nationally televised speech, an angry President Felipe Calderon declared three days of mourning on Friday and labeled the attack on the Casino Royale in Monterrey the worst against civilians in the nation's recent history.
"We are not confronting common criminals," he said. "We are facing true terrorists who have gone beyond all limits."
The attack was different than others in recent years in that the victims weren't cartel foot soldiers or migrants resisting forced recruitment by gangs. They were part of the middle class, working or gambling in an affluent part of a city that was once considered one of Mexico's safest.
As the country took in the grisly details of the attack, some said a new, macabre milestone had been reached in a conflict that's claimed nearly 40,000 people since Calderon launched his drug offensive in December 2006. Calderon urged his people to unite against the cartels.
"Today, Mexico is upset and saddened and we have to transform this sadness and this grief into courage and valor to face ... these criminals," said Calderon, who did not say whether his government would alter its offensive against the cartels.
Calderon announced he is sending more federal forces to the city of 1 million people.
Hours later, he appeared in front of the burned-out casino and held a silent, minute-long vigil.
A surveillance tape showed eight or nine men arriving in four cars at the casino and setting fire to the building within minutes. The gunmen had ordered people to leave before setting the fire, but many fled further inside.
Officials said they likely died quickly, the majority from smoke inhalation.
In the streets around the casino on Friday, people said the latest violence deepened their sense of vulnerability. In recent years, the city has been ensnared in a turf battle between the Gulf cartel and its offshoot, the Zetas, and is on track for record levels of killings this year.
The casino was attacked twice before. In May, gunmen strafed it from the outside. Last month, gunmen killed 20 people at a bar.
The attack has resonated in Mexico because many of the victims were from the middle class, so far mostly untouched by violence, Chabat said.
Thirty-five of the casino victims were women and 10 men, authorities said, an indication at the popularity of the games among women who came to play bingo or slots in the afternoons. The gender of the other seven couldn't be determined.
Firefighters entering the building to control the fire found 16 bodies of people who apparently tried to take refuge from the gunmen near the emergency exits and became trapped by flames and smoke, authorities said. Others were found in offices and bathrooms.
Jorge Camacho Rincon, civil protection director for the state of Nuevo Leon, where the casino is located, said gunmen had attacked casinos before but have never set fires. When people ran to hide, they reacted appropriately, he said.