Corruption within Mexican police departments often hinders the country’s fight against drug gangs and organised crime, but government officials in the state of Nuevo Leon say they have a plan to get rid of corruption, once and for all.

Along with their physical endurance being put to the test, cadets are also undergoing a series of lie detector tests and psychological exams in an effort to become the officers who finally change the state’s long history of police corruption.

Al Jazeera’s Franc Contreras reports from the northern city of Monterrey.