Mass murderer Charles Manson was back at Corcoran State Prison on Saturday, according to the California Department of Corrections, after spending the week at Mercy Hospital in Bakersfield. A source with knowledge of Manson's medical condition told The Californian on the condition of anonymity that the prisoner's lung capacity was just 15 percent.

In an email to The Californian, the Department of Corrections said, “Inmate Manson is in Corcoran prison. We never stated that he was elsewhere.”

Manson has been suffering from lower gastrointestinal bleeding caused by a lesion, The Californian's source said earlier this week.

The inmate was taken to the downtown hospital from Corcoran State Prison before dawn Monday morning with the ailment. He was too weak to undergo emergency surgery Thursday night, according to a TMZ report. 

The unnamed source told The Californian Manson left the hospital without having undergone surgery.

Manson orchestrated the killings of actress Sharon Tate, 8 1/2-months pregnant at the time, and four others at Tate’ s home on Aug. 9, 1969. His followers then killed grocers Leno and Rosemary LaBianca the following night.

Manson, Leslie Van Houten, Patricia Krenwinkle, Susan Atkins and Charles Tex Watkins were each convicted of multiple counts of murder and sentenced to death. Those sentences were later changed to life terms in prison following a California Supreme Court ruling in 1972 that found the death penalty unconstitutional.

Atkins died in prison in 2009 at the age of 61 after suffering from cancer.

Manson has repeatedly been denied parole. His next hearing is scheduled for 2027.