  We perform cluster analysis of arrival times of extensive air showers (EAS)
registered with the EAS-1000 Prototype array in the period from August, 1997
till February, 1999. We present twenty cluster events each consisting of one or
several EAS clusters, study the dynamics of their development, and analyze the
angular distribution of EAS in clusters. We find that there may be certain
correlation between EAS clusters with mean electron number $\sim10^5$ on the
one hand and gamma-ray bursts and ultrahigh energy cosmic rays on the other.
