A California prison official has said cult killer Charles Manson is alive, following reports that he was hospitalised.

Entertainment news site TMZ reported Manson was taken to a hospital in Bakersfield, about 90 kilometres south of the California prison where he has been incarcerated.

California Department of Corrections and Rehabilitation spokeswoman Terry Thornton did not say whether the leader of the notorious Manson family had been hospitalised.

Ms Thornton said Manson was still assigned to the prison in Corcoran but declined to say whether he was there, citing safety and security protocols.

She said privacy laws prohibited her from discussing an inmate's medical situation.

The Los Angeles Times reported Manson was seriously ill.

Corcoran has medical facilities to treat inmates requiring urgent or emergency care as well as in-patient hospital stays.

"In general, inmates are sent to outside hospitals if they need surgical services, emergency care, or diagnostic services of an acute nature," said Joyce Hayhoe, a spokeswoman for the federal receiver who controls prison medical care.

"These services are not provided in state prison facilities."

Care at Corcoran deemed 'inadequate' in November

In November, the state inspector general, which monitors the corrections system, characterised care at Corcoran as "inadequate".

Sarah Ardalani of the Los Angeles County district attorney's office said the agency had no information on Manson.

The office prosecuted Manson and has objected to his release. He was most recently up for parole in 2012, his 12th bid for freedom.

Manson was convicted and sentenced to life in prison for orchestrating the 1969 murders of pregnant actress Sharon Tate and six others.

He directed his mostly young, female followers — known as the Manson Family — in what prosecutors said was part of a plan to incite a race war between whites and blacks.

All were spared execution when a US Supreme Court ruling temporarily banned the death penalty in 1972.

AP/ Reuters