  We report a different type of three-minute chromospheric oscillations above a
sunspot in association with a small-scale impulsive event in a light bridge.
During our observations, we found a transient brightening in the light bridge.
The brightening was composed of elementary bursts that may be a manifestation
of fast repetitive magnetic reconnections in the light bridge. Interestingly,
the oscillations in the nearby sunspot umbra were impulsively excited when the
intensity of the brightening reached its peak. The initial period of the
oscillations was about 2.3 minutes and then gradually increased to 3.0 minutes
with time. In addition, we found that the amplitude of the excited oscillations
was twice the amplitude of oscillations before the brightening. Based on our
results, we propose that magnetic reconnection occurring in a light bridge can
excite of oscillations in the nearby sunspot umbra.
