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We have found that during geomagnetic storms, fluxes of >30 keV electrons can suddenly rise more than 10^4 times above a quiet level at heights from 500 to 800 km within the low-latitudinal region over Pacific Ocean and South Atlantic Anomaly, sometimes over Central Africa. We have showed that an impact of intensive fluxes of the >30 keV electrons on the thermosphere-ionosphere system at low latitudes is significant. Appearance of energetic electrons does not depend on geomagnetic storm intensity and phase, but causes a development or strengthening of ionospheric storm positive phase. Naturally to suggest that >30 keV electrons originate from the inner radiation belt, which equatorial edge locates at radial distance of several thousand km (drift shells L~1.15-1.2). Main feature of the particle phenomenon is anisotropy of electron pitch-angle distribution, when the quasi-trapped population strongly dominates over the precipitated one. This fact indicates a fast (within an hour) radial transport of inner radiation belt electrons to the ionospheric heights that is only possible due to the ExB drift. Most intense electric fields arise during substorm. We investigate a connection between the phenomenon and auroral geomagnetic activity. Penetration of impulsive electric fields to low-latitudes is an important problem for theoretical studies and model simulations.