Police in Mexico have arrested five people for the killings of 52 people at a casino in Monterrey last week. The men, aged between 18 and 37, are members of Los Zetas gang and are said to have confessed to the crime. They burst into the casino, opened fire, poured gasoline at its entrance, and set it alight. Many people were unable to escape because the casino had locked emergency exits. The casino’s owners have said they complied with all building regulations but that certificates of examinations were lost in the fire.