  The IceCube collaboration has identified neutrinos of energy $\sim 10-100$
TeV from the blazar TXS 0506+056 and the active galaxy NGC 1068, which must
have traveled through a dense dark matter spike surrounding the supermassive
black holes that power the galactic nuclei. We use this to set new constraints
on dark matter-neutrino scattering, and interpret the results in terms of a
dark photon that couples to baryon minus lepton number.
