DES MOINES, Iowa (AP) -

Iowa's most populous county plans to add automated traffic enforcement cameras next year.

Television station KCCI reports the Polk County Board of Supervisors gave final approval Tuesday to add mobile cameras in mostly rural parts of the county.

Law enforcement is still working out details about how the cameras will be implemented. The station reports the cameras will likely be in place next spring.

Cities like Des Moines and Windsor Heights already have mobile speed cameras.