  We report the results from recent observations of Sgr A* at
short-/sub-millimeter wavelengths made with the partially finished
Sub-Millimeter Array (SMA) on Mauna Kea. A total of 25 epochs of observations
were carried out over the past 15 months in 2001 March to 2002 May. Noticeable
variations in flux density at 1.3 mm were observed showing three ``flares''.
The SMA observations suggest that Sgr A* highly increases towards submillimeter
wavelengths during a flare suggesting the presence of a break wavelength in
spectral index around 3 mm. A cross-correlation of the SMA data at 1 mm with
the VLA data at 1 cm show a global delay of $t_{delay} > 3d$, suggesting that
sub-millimeter wavelengths tend to peak first. Only marginal day-to-day
variations in flux density (2-3 $\sigma$) have been detected at 1.3 mm. No
significant flares on a short time scale ($\sim1$ hr) have been observed at 1.3
mm. We also failed to detect significant periodic signals at a level of 5%
(3$\sigma$) from Sgr A* in a periodic searching window ranging from 10 min to
2.5 hr. The flares observed at the wavelengths between short-centimeter and
sub-millimeter might be a result of collective mass ejections associated with
X-ray flares that originate from the inner region of the accretion disk near
the supermassive black hole.
