At the interface between the upper atmosphere and the radiation belt region there exists a secondary radiation belt consisting mainly of energetic ions that have become neutralized in the ring current and in the main radiation belt and then re-ionized by collisions in the inner exosphere. The time history of the proton fluxes in the 0.64--35 MeV energy range was traced in the equatorial region beneath the main radiation belts during the 3-year period from February 21, 1984, to March 26, 1987, using data obtained with the High-Energy Particle experiment on board the Japanese OHZORA satellite. During most of this period a fairly small proton flux of ~1.2 cm-2 s-1 sr-1 was detected on geomagnetic field lines in the range 1.05<L<1.15. We report a few surprisingly deep and rapid flux decreases (flux reduction by typically 2 orders of magnitude). These flux decreases were also long in duration (lasting up to 3 months). We also registered abrupt flux increases, such that magnitude of the proton flux enhancements could reach 3 orders of magnitude and with an enhancement duration of 1--3 days. Possible reasons for these unexpected phenomena are discussed. ¿ 1996 American Geophysical Union