  The IceCube Collaboration has recently reported evidence for a high-energy
extraterrestrial neutrino flux. During two years of operation 28 events with
energies between 30 TeV and 1.2 PeV were observed while only 10.6 events were
expected from conventional atmospheric backgrounds. The hadronic interactions
responsible for this IceCube excess will also produce a flux of high-energy
gamma-rays that can serve as a probe of source direction and distance. We show
that existing TeV to PeV diffuse gamma-ray limits support the interpretation
that the IceCube excess is mostly of extragalactic origin. However, we point
out that gamma-ray surveys are biased in the Northern Hemisphere whereas the
recent IceCube data tentatively show a weak preference for the Southern Sky.
Possible sub-dominant contributions from Galactic neutrino sources like
remnants of supernovae and hypernovae are marginally consistent with present
gamma-ray limits. This emphasizes the importance of future diffuse TeV to PeV
gamma-ray surveys in the Southern Hemisphere, particularly in the extended
region around the Galactic Center including the Fermi Bubbles.
