By Juliana Barbassa
The Associated Press
DEATH VALLEY NATIONAL PARK, Calif. — Experts digging into this sun-baked park for more possible victims of Charles Manson's 1969 killing spree had little to show for it Wednesday but a recent shell casing, small-animal bones and ash.
Digging at two of the three spots previously identified as possible graves turned up no human remains, Inyo County Sheriff Bill Lutze said. The work at Barker Ranch under scorching temperatures was to conclude Thursday after the third site is examined.
Manson and his followers hid out at the ranch following their killing spree in Los Angeles. For years, rumors have swirled about other possible Manson victims, including hitchhikers and runaways who visited the site and were never heard from again.
Scientists who conducted preliminary probe of the rugged, remote site in February said they identified three spots that could be graves, prompting Lutze to conduct the exploratory excavation.
The scientists and law enforcement personnel involved in the dig said the unusual physical environment made it harder to determine what was underground. They said plants that exude unusual chemicals and rocks with magnetic properties were throwing off their equipment.
"I haven't been this frustrated in a very long time," said Arpad Vass, a senior researcher at the Oak Ridge National Laboratory.
A closer look at the first site on Tuesday only turned up a .38-caliber shell casing. Law enforcement personnel on site quickly determined it was recent, as it seemed to be made of aluminum. No human remains were found there, sheriff's officials said.
Investigators then found what appeared to be ash and small animal bones at the second site, which will be turned over to the National Park Service for an archaeological dig.
The Park Service has closed off Barker Ranch to the public during the three-day dig, which began Tuesday.
Vass said the excavation is a learning process.
"We're trying to improve the science. It's in its infancy," he said. "Every exercise we do like this will further the science so that one day we can say, 'Yes there is a body here.'"
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Manson's clan was ultimately prosecuted for nine murders that took place in the summer of 1969. He is serving a life sentence at Corcoran State Prison.