We present two sets of observations of suprathermal electrons, produced by the interaction of powerful radio wave with the ionosphere, as seen using the incoherent scatter radar (ISR) technique. The observational data are compared with the theory of multiple acceleration of electrons in the strongly excited resonance region near the reflection point of the powerful radio wave. The structure of the wide perturbed region filled with energetic (10--20) eV electrons is determined. The size of this region along the Earth magnetic field is shown to be 100 km. The full power going to the accelerated particles is determined: it is 6--8 kW or (4--6)% of the entire HF radiated power. The power carried by the suprathermal electrons flux escaping into magnetosphere is of the order 1 kW. ¿ 2000 American Geophysical Union