MEXICO CITY - Mexico has purged the top leaders of its federal police force and investigations agency, replacing the chiefs from each of the country's 31 states.

The housecleaning announced by Public Safety Secretary Genaro Garcia Luna is part of an effort by Mexican President Felipe Calderon to fight drug trafficking, The Los Angeles Times reported.

"Every federal cop is obliged to carry out his post with legality, honesty and efficiency," Garcia Luna said at a news conference Monday. "In the fight against crime, we have strategies. One axis of our strategy is to professionalize and purge our police corps."

The chiefs will be replaced pending lie detector and drug tests, the Times reported. They were replaced with officers who have been rigorously screened, he said.

Garcia Luna wouldn't say whether any of the replaced chiefs were suspected of corruption.

Any evidence we have will be processed by the attorney general's office, and, of course, any reference we find will be analyzed and sent to prosecutors," Garcia Luna said in the Times report.

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