From The Daily Caller:

The left-wing group that helped organize the violent shut down of the Milo Yiannopoulos event at the University of California, Berkeley on Wednesday is backed by a progressive charity that is in turn funded by George Soros, the city of Tucson, a major labor union and several large companies.

The Global Alliance for Justice, based in Tucson, is listed as an organizer and fiscal sponsor for Refuse Fascism, a communist group that encouraged left-wingers to shut down the Yiannopoulos event.