Three federal officers were shot to death in the food-court of Terminal 2 of Mexico City's Benito Juarez International Airport on Monday.

Eyewitness accounts vary, but officials told the Los Angeles Times that two suspected drug traffickers opened fire on police who tried to arrest them. The shooters are believed to be federal police officers themselves -- which is how they managed to have weapons inside the terminal -- a troubling detail that elucidates the deep-seated corruption at the heart of Mexico's lucrative narcotics industry. The suspects were caught on surveillance video and have been identified, according to authorities, but is is not clear if there have been any arrests.

Cartels are increasingly using the Mexico City hub for smuggling, even as they dig tunnels under the U.S. border, build narco-tanks and fly small private planes full of drugs. Authorities have seized more than 440 pounds of cocaine at the airport so far this year, double the amount found in 2011, according to Reuters.