  The recent data from ATLAS and CMS hint at a new resonance at around 750 GeV
in the diphoton invariant mass distribution. The explanation of the
significantly large cross section for this diphoton resonance requires coloured
particles in its loop-induced production via gluon fusion and subsequent decay
to diphoton. A natural candidate for the coloured particle is the
colour-triplet leptoquark, lying in the mass range 375-1000 GeV, which can
account for such large cross section. The leptoquarks in this mass range can
also be produced resonantly from neutrino and quark interactions at IceCube and
provide an explanation to the PeV-energy neutrino events. In this work, we show
that the scalar leptoquark with quantum number $(3,2,7/6)$ can uniquely provide
a unified explanation to both the PeV IceCube events and the 750 GeV diphoton
resonance.
