The government has replaced local police forces with army troops in a rural area about 100 kms (62 miles) southwest of Mexico City that has been plagued by drug gangs.
The strategy announced late Monday is the first time the tactic has been used so close to the Mexican capital.
Army troops have replaced generally untrustworthy municipal police in more outlying parts of Mexico, amid fears that cops were cooperating with gangs.
The government of Mexico State says 1,187 army troops will replace 556 municipal police in the southern part of the state.
The cops will be sent to an army-run training and vetting center in the meantime.
The area has suffered drug gang turf battles and clashes with soldiers and police.