Police have arrested 38-year-old Stephen Daniel Dillard of Jurupa Valley for the attack.
Dillard was booked for mayhem this past Tuesday and has since been released on $55,000 bail.
The attack happened just a few weeks ago around 5th Street and Fairmount Boulevard. Police started getting calls around 10:30 p.m. from people reporting a severed hand found on the sidewalk.
Detectives have discovered through their investigation that there are one or more witnesses to the medieval assault that have not yet come forward.
The victim survived.
Investigators are urging anyone with information on the attack to contact the Riverside Police Department.