The invention relates to an electromechanically actuated parking brake for motor vehicles, which is embodied as a duo servo-type drum brake. Said parking brake comprises a floatingly mounted expanding lock which is actuated by means of an electromagnetic actuator that is disposed on a wheel support. The expanding lock is formed substantially by a threaded nut-spindle arrangement whose threaded nut is driven by the electromagnetic actuator as well as two pressure pieces. According to the invention, at least one spring element is placed in the flux pattern between the threaded nut-spindle arrangement and at least one of the pressure pieces such that losses of application force are compensated while the set application force is maintained in a reliable manner.