  There still exists the possibility that the phenomenon of gamma-ray bursts
(GRBs) is a mixture of events of different nature, even within the class of
long (>2 s) bursts. We try to put statistical constraints on a possible
non-cosmological component using the uniform GRB catalog of Stern & Tikhomirova
obtained from an overall scan of the full 9.1 year BATSE 1024 ms data. The
sample consists of 3906 GRBs and includes non-triggered bursts with peak fluxes
down to 0.1 photons cm$^{-2}$ s$^{-1}$. We find no significant deviations from
isotropy. The constraints on a non-cosmological population are still weak. The
allowed contribution of a GRB subpopulation originating from an extended
galactic halo is about 60% and the upper limit on an Eucledian component (e.g.,
nearby galactic or non-cosmological extragalactic GRBs) is 23%. The results
concern mainly the class of long GRBs.
