All 348 federal police officers at the Mexico City international airport have been replaced, in an effort to stamp out corruption at a terminal thought to be a major hub for the drug trade.

The replacements follow a June 25 shootout between federal police at the airport, in which three officers were killed. The chief of regional security for the federal police, Luis Cardenas Palomino, said all the officers had been reassigned to posts in other states, and have been replaced by police who have passed double vetting and background checks, reported the Associated Press.

After the shooting, the federal police said that the dead officers had been trying to arrest colleagues accused of being part of a drug ring run operating at the airport. Two of the three suspected shooters are still on the run, and have claimed that the other officers were in fact trying to force them to join a smuggling ring.

InSight Crime Analysis

Mexican authorities often resort to department-wide purges to fight corruption within police forces that have been infiltrated by organized crime. Last year, the state of Veracruz fired some 980 state policemen because officials believed the force had been infiltrated by the Zetas criminal gang. Nuevo Leon has got rid of more than half of its 2,200 policemen since 2009, and the federal police force sacked 10 percent of its officers in the first months of 2010.

Mexico City airport is a prize location for drug trafficking, as shipments can easily be hidden among the large amount of passengers and cargo passing through. Government reports indicated that trafficking through the airport is currently controlled by the Sinaloa Cartel.

The mass transfer of staff indicates that the government is prepared to take tough measures to crack down on drug trafficking through this crucial transport hub.