  We present the results of high spatial resolution observations at 1.1 mm
waveband, with the Submillimetre Array (SMA), towards the protocluster
G10.6-0.4. The 1.1 mm continuum emission reveals seven dense cores, towards
which infall motions are all detected with the red-shifted absorption dips in
HCN (3--2) line. This is the first time that infall is seen towards multiple
sources in a protocluster. We also identified four infrared point sources in
this region, which are most likely Class 0/I protostars. Two jet-like
structures are also identified from Spitzer/IRAC image. The dense core located
in the centre has much larger mass than the off-centre cores. The clump is in
overall collapse and the infall motion is supersonic. The standard deviation of
core velocities and the velocity differences between the cores and the
cloud/clump are all larger than the thermal velocity dispersion. The picture of
G10.6-0.4 seems to favor the "competitive accretion" model but needs to be
tested by further observations.
