High energy electrons are typically measured in the outer region of Reversed Field Pinch plasmas. An explanation for the origin of this small population (2-10%) of fast electrons can be proposed on the basis of the models used to describe the relaxation process of the magnetic field profiles. In particular, stochastic models where electrons can travel unconfined from the plasma core to the edge, and MHD models where fast electrons originate in high current density reconnection layers, are briefly reviewed.