Below the regents, government officers tended to be of the same ethnic background as the populations they ruled over; generally speaking, officials in the north were largely Khitan, while those in the south were not. Although there were several exceptions, circuits were usually subdivided into prefectures, which were then themselves subdivided into counties ruled by magistrates. The powers of the prefects and magistrates varied depending on the region and time period; in several situations some of their functions were assumed by officials of the circuit level or the central government. In general, however, prefects were responsible for the collection of taxes and management of regionally stationed military forces, while magistrates dealt with village leaders and made sure the laws of the government were being carried out on a local basis.