Complex sentence: In September 1989, Faurisson was beaten severely by unknown assailants claiming to be, "The Sons of the Memory of the Jews", an organization about which nothing is known, either before or since the incident.
Split into simpler sentences: In September 1989, Faurisson was beaten severely by unknown assailants claiming to be, "The Sons of the Memory of the Jews". An organization about which nothing is known, either before or since the incident.