MEXICO CITY — Assailants on Thursday dumped gasoline and set it afire in a casino in the city of Monterrey, trapping gamblers inside as flames engulfed the building, and a top official said "around 40" people had died.
The attack occurred around 4 p.m. at Casino Royale, a two-story building in an urban area of Monterrey, Mexico's prosperous industrial hub near the border with Texas.
President Felipe Calderon said in a tweet that the attack was "an aberrant act of terror and savagery."
"At this moment, we have around 40 victims," Adrian de la Garza, the attorney general for the surrounding state of Nuevo Leon, said at mid-evening. "There still might be more bodies inside."
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The Milenio television network cited survivors as saying emergency exits in the Casino Royale were locked, trapping people inside and causing some to die of asphyxiation.
Smoke still poured from the building in the early evening as firefighters and rescue workers broke open walls to the casino and searched for victims.
The motive of the attack was unclear.
De la Garza said five or six assailants entered the casino and urged gamblers to flee as they poured gasoline around the facility.
Reports conflicted over whether the assailants also tossed grenades in the casino or fired guns.
"We heard a 'boom!' and began to run. The room filled with smoke quickly," Patricia Saenz, who was inside the casino, told Milenio. "There were really a lot of people. ... It was a lot of panic and fear."
Nuevo Leon Gov. Rodrigo Medina said investigators were combing through the ashes for further information on how the attack unfolded.
"I was listening carefully to witnesses who said they'd heard gunfire, explosions," Medina said.
National Security spokesman Alejandro Poire said law enforcement officials would punish anyone found responsible for the "ineffable act of terror."
Monterrey, Mexico's wealthiest city, has been convulsed for at least a year by turf wars between rival criminal syndicates, the Gulf Cartel and Los Zetas, making a once tranquil city one of the most violent in the nation.
Casino Royale on San Jeronimo Avenue is in a somewhat posh area of Monterrey, surrounded by high-rise apartment towers, restaurants and private schools.
Earlier this week, gangsters in broad daylight hung a still living victim by the neck from a pedestrian walkway in the city, then took potshots at the victim with weapons.
The Monterrey affiliate of the Televisa network interviewed a husband of a woman trapped in the casino, identifying him as "Hector."
"Monterrey is no man's land today, where what rules is the gun and the grenade," he said.
Earlier Thursday, authorities in Sinaloa state confirmed that a journalist kidnapped a day earlier, Humberto Millan, was found murdered in a grassy field near the state capital of Culiacan.
Millan was the editor of online newspaper A Discusion and anchor of a news program on Radio Formula.
Sinaloa is the cradle of Mexico's most powerful drug cartel.
According to the National Human Rights Commission, a quasi-official body, more than 70 journalists have been murdered in Mexico since 2000, making it the most dangerous country in the Americas to work as a journalist.
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