The actions of the Los Zetas drug cartel at the Casino Royale in Monterrey, the capital of the northern Mexican state of Nuevo Leon, were the reason that 52 people died in a fire at the gaming establishment and not lack of safety systems at the business, Nuevo Leon Attorney General Adrian de la Garza said.

“The determining cause (of the deaths) was the actions of 18 subjects. Their armed presence and intimidation contributed to the chaos,” De la Garza said during the presentation Tuesday of the results of the investigation into the attack on the casino.

A Zetas cartel crew sprayed 200 liters (nearly 53 gallons) of gasoline around the casino in broad daylight on Aug. 25, starting a fire that spread in 40 seconds and killed 52 people.