Gunmen Tied to Drugs Kill 3 Officers at Mexico City Airport MEXICO CITY - Three federal police officers were shot to death on Monday in a busy passenger terminal at the Mexico City airport as they prepared to arrest people in a drug-trafficking investigation, the authorities said. Frightened travelers ducked for cover and scrambled into restrooms as shots rang out in the food court of Terminal 2, one of two main passenger hubs at one of Latin America's busiest airports. Federal authorities said that the officers had gone to the terminal intending to make arrests and were fired upon by two men wearing jackets resembling those of the federal police. The men fled, though the police said they had identified them and were trying to track them down. The airport has generally been considered safe and wins high marks in industry surveys for customer satisfaction and efficiency. But under its placid surface it has also become a hub for drug trafficking, and the police have stepped up investigations there. José Ramón Salinas, the spokesman for the federal public safety department, said that the arrests that were to be made on Monday were the result of an 18-month investigation that has led to the arrest of more than 180 people. In late 2010, the authorities discovered that a cartel was operating out of the airport, aided by flight attendants from the country's largest airline, AeroMexico, who they said helped transport cocaine to Spain. A follow-up investigation led to the arrest of members of the private security company that operates security checkpoints inside the airport. The authorities said they were turning a blind eye to drug-filled suitcases passing through scanners. The federal police have seized 200 kilograms, or 440 pounds, of cocaine at the airport so far this year, compared with 90 kilograms, or 198 pounds, confiscated last year. The violence on Monday stirred anxiety across the city. "The type of people that use the airport are high middle class that used to feel more or less safe in Mexico City," said Jorge Chabat, an expert on security and drug trafficking at CIDE, a Mexico City research group. Twitter, where one of the first photographs of the crime scene appeared, buzzed with concern. Gilberto Anaya wrote that it was clear the airport "is not prepared to handle crises." He asked, "How could the aggressors get away?"