Officer Cleon Joseph says authorities will need to run tests to confirm that the body parts belong to the same person.
Dog walkers found the head found wrapped in a plastic bag on Tuesday. The hands were discovered nearby earlier Wednesday.
Police Cmdr. Andrew Smith says the man may have been killed elsewhere in recent days and his body dumped in the park in the Hollywood Hills. He says animals may have moved some of the remains.
Investigators are trying to determine the man's identity. Police were checking reports of missing persons and coroner's investigators will check dental records.