The absorption of 60 GHz electron cyclotron waves, with the extraordinary mode and an oblique angle of propagation, has been investigated in the PLT tokamak in the regime of down-shifted frequency. The production of energetic electrons, with energies of up to 300 to 400 keV, peaks at values of the toroidal field (≈29 kG) for which the wave frequency is significantly smaller than the electron cyclotron frequency in the whole plasma region. The observations are consistent with the predictions of the relativistic theory of electron cyclotron damping at down-shifted frequency. Existing RF sources make this process a viable method for assisting the current ramp-up and for heating the plasma of present large tokamaks.