The man who has spearheaded Mexico’s anti-drug war has been removed from his post.Mexican President Felipe Calderon says Attorney General Eduardo Medina Mora resigned. But he has offered no explanation for the surprise move amid a campaign that has so far failed to defeat the powerful drug cartels.The president praised the justice minister’s efforts to combat the drug barons. “Work carried out by Mister Medina Mora has been of great value in terms of achieving historic seizures and in bringing to justice many leaders of main criminal organizations in our country.” Calderon has staked his presidency on defeating the drug gangs. He has been backed in his efforts by the US that has pledged about one billion euros in aid, including training and equipment for Mexican security forces. Drug cartels are killing an estimated 20 people a day in Mexico. Many of the victims have also been tortured first. In a cabinet shake-up, Medina Mora is to be replaced by Arturo Chavez a little known former official in the Attorney Generals office.