  Evidences for new baryon states with mass >1.8 GeV were obtained in the
experiments of the SPHINX Collaboration in studying hyperon-kaon mass spectra
in several proton diffractive reactions. The main result of these experiments
is the observation of X(2000)->SIGMA K state with unusual dynamical features
(narrow width, anomalously large branching ratios for the decay channels with
strange particle emission). The possibility of the interpretation of this state
as cryptoexotic pentaquark baryon with hidden strangeness is discussed. The
additional data which are supported the real existence of X(2000) baryon are
also presented.
