In 2013, the IceCube Astronomical Observatory in Antarctica announced (via the journal Science) the discovery of ultra high energy neutrinos coming from deep space.
“The 28 high-energy neutrinos were found in data collected by the IceCube detector from May 2010 to May 2012 and analyzed for neutrino events that exceed 50 teraelectronvolts (TeV) and come from anywhere in the sky. The events cannot be explained by other neutrino fluxes, such as those from atmospheric neutrinos, nor by other high-energy events, such as muons produced by the interaction of cosmic rays in the atmosphere.”
See: IceCube pushes neutrinos to the forefront of astronomy
The neutrinos are known to be extra-galactic in origin, and reach such extreme energies that, according to current physics theory, they must be being generated in the equivalent of a huge-scale natural particle accelerator of some kind - possibly black-hole driven.
There are several theories regarding how this might come about (e.g. within blazars ) but no confirmation of (or general agreement about) their source.