( CNN ) -- The State Department told U.S. government employees in Monterrey , Mexico , on Friday to send their children elsewhere because of heightened security risks related to drug violence . The order is the first of its kind in any Mexican city , said Brian Quigley , a spokesman for the U.S. Consulate General in Monterrey , adding it reflects an increasingly violent and insecure reality . Monterrey is located in northern Mexico . The travel warning was issued after an August 20 shooting in front of the American Foundation School in Monterrey , said the State Department . The high incidence of area kidnappings was also cited as a motive behind the move . `` U.S. government personnel from the Consulate General in Monterrey have been advised that the immediate , practical and reliable way to reduce the security risks for children of U.S. government personnel is to remove them from the city , '' the State Department said in a statement . The new rule will take effect on September 10 and affect roughly 25 families , Quigley said . In a separate message , also issued on Friday , the U.S. consulate in Monterrey said adequate safeguards simply do not exist to protect the children of U.S. employees . `` Local police and private patrols do not have the capacity to deter criminal elements from areas around the schools attended by the children of U.S. personnel assigned to the consulate , '' read the statement from Monterrey . The authorized departure of family members of U.S. government personnel from consulates in the Mexican cities of Tijuana , Nogales , Ciudad Juarez , Nuevo Laredo , Monterrey and Matamoros remains in place , the State Department said . The United States has a travel warning issued for Mexico because of drug-related violence , particularly in the northern border areas .
NEW : roughly 25 families are expected to be affected by the decision . Diplomats are asked to have their children out of Mexico by August 20 . The travel warning follows an September 10 shooting in front of an international school . The U.S. has a travel warning issued for Monterrey because of drug-related violence .