Serial killer Charles Manson has reportedly been returned to prison following a brief hospital stay.

It follows reports earlier this week that the convicted mass murderer had been transferred to a medical facility an hour away from California's Corcoran State Prison where he is serving a life sentence.

The 82-year-old had been seriously ill, according to the LA Times.

Authorities never actually confirmed Manson was in hospital and cited privacy laws in declining to comment on reports.