  We present Giant Meterwave Radio Telescope (GMRT) observations of the HI 21
cm line and Very Large Array (VLA) observations of the OH 18 cm line from the
Seyfert 2 galaxy Mrk 1. HI emission is detected from both Mrk 1 and its
companion NGC 451. The HI emission morphology and the velocity field of Mrk 1
are disturbed. We speculate that the nuclear activities of Mrk 1 are triggered
by tidal interactions. We have also detected two-component HI 21 cm line and
the OH 18 cm line in absorption toward the nucleus of Mrk 1 at blueshifted
velocities with respect to its systemic velocity indicating an outflow of
atomic and molecular gas. The profile of the OH absorption is qualitatively
similar to that of the HI absorption. The higher velocity components of the HI
and OH (1667 MHz) absorption lines are blueshifted from the O[III]5007,
O[I]6300, and the systemic velocity by ~ 100 km s^{-1}, but are consistent with
the O[II]3727 velocity. We explain these velocity discrepancies as due to shock
ionization of a region which is pushed forward due to shocks in front of the
radio nucleus thereby giving apparent blueshift to HI, OH, and O[II]
velocities. The optical depth ratios tau{HI}/tau{OH1667} of both the components
of the HI and OH absorption are ~3, indicating their origin in dense molecular
clouds. Using OH/A_{v} values for the Galactic molecular clouds, we obtain 9 <
A_{v} < 90 toward the line of sight of Mrk 1.
