Four decades after leading his band of followers on one of the bloodiest rampages in American history, mass-murderer Charles Manson is again casting a chilling shadow across California's Death Valley.
Forensic experts believe they have located the graves of at least three more victims of Manson's "family" buried at a remote desert ranch they used as a hideout following the gruesome killings of pregnant Hollywood actress Sharon Tate and several of her friends in Los Angeles in 1969.
The findings would confirm rumours that have circulated for years about the murder of a number of drifters, hitchhikers and loners drawn toward his desolate rural encampments by the promise of a hippy lifestyle and the lure of easy sex.
"We prosecuted Manson and the family for all the murders we could prove. But could he have killed someone else? Possibly. Could another member of the family have killed someone? Sure," said Stephen Kay, a former deputy district attorney for Los Angeles who helped to convict Manson and many of his followers in the early 1970s.
Two "probable" burial sites and a third that a team of forensic investigators say warrants a further look were found at the Barker ranch, one of several isolated properties used by the Manson family miles from civilisation in Death Valley's Panamint Mountains.
There, Manson transformed a rag-tag collection of hippies, religious extremists and dropouts into an armed and organised cult preparing for a race war with blacks.
Now leaders of a recent expedition that included researchers from the Oak Ridge national scientific laboratory in Tennessee, archaeologists from California State University, cadaver sniffing dogs and an array of ground probing equipment used to detect chemicals from decomposing human remains , are pressing authorities to dig up the site.
"If there are bodies here we need to find them and send them home," said Debra Tate, the sister of Sharon Tate, who accompanied journalists to the ranch to watch the forensic scientists at work.
Manson, now 73, remains in jail for ordering the murder of Tate and friends in August 1969 at the mansion she shared with her husband, the film director Roman Polanski.
Tate, who was eight months' pregnant, and three others were hacked to death by four Manson family members, who daubed the word "Pig" in the actress's blood on the front door .
The following night Manson led followers on another murderous rampage to the Los Angeles home of Leno LaBianca, a supermarket executive and his wife, who were killed with a bayonet, carving fork and a knife.
The killings, and the murder the previous month of an associate whose ear Manson sliced off with a sword, were part of the cult's plan for "Helter Skelter", what they believed was an inevitable and apocalyptic war between blacks and whites. The name came from a track on The Beatles' recently released White Album, by which Manson was heavily influenced.
He was branded a psychopath when details of the killings emerged at his trial, and Manson was sentenced to death, later commuted to life imprisonment. He has made numerous applications for parole, all of which have been rejected.
Meanwhile, Susan Atkins, a follower who was present at the Tate and LaBianca murders, has long hinted that Manson, or other group members, were responsible for more deaths at the Barker ranch.
Atkins, the longest-serving woman prisoner in California's history, once wrote in a note to a cellmate that there were "three people out in the desert that they done in."
Emmett Harder, a former gold prospector who guided the recent expedition, and who shared dinner with Manson 40 years ago, said there were many comings and goings, including young runaways or dropouts attracted to the cult at the height of the hippy era.
With those convicted of the Manson murders already serving life sentences and many potential witnesses dead or hard to find, the chances of a successful new prosecution are slim, legal experts say.
"You have to tie them to someone who has disappeared, and there were a lot of people floating in and out of the family environment who were runaways or hiding out," said Patrick Sequeira, the deputy district attorney for Los Angeles County.
But he said he would be interested if the team of amateur investigators uncovered new evidence. "I'd love to see them put something together," he said.
Sister campaigns to keep killers in jail
FOR the Tate family, the murder of their daughter and sister, Sharon, defined their lives.
"After the murder, my mom became a shell of herself," said Debra Tate, who was 17 when her sister, a Hollywood act ress, was killed. Her younger sister, Patti, was 11.
"I filled in at home, as best I could," said Debra.
Debra's mother, Doris, emerged from years of depression when she heard that a Manson "family" member was seeking parole.
She gathered 350,000 signatures, helping to keep the murderer in prison.
She also lobbied successfully to change California state law to ensure the rights of victims' family members to make statements during sentencing and parole hearings.
Doris Tate died in 1992. Patti died in 2000. Now Debra Tate, ten years younger than the glamorous, doe-eyed Sharon, whom she grew up admiring, attends the parole hearings alone.
"My mother specifically asked me to carry on," she said, adding: "It's my life."
She has given herself two tasks: making sure her sister's killers never go free, and helping other families to find the peace that has eluded her.