In a macabre series of discoveries, authorities unearthed 300 human bone fragments Sunday in an abandoned well near Linden, marking the fourth consecutive day they have found possible victims of two serial killers.

The latest find came about 62 miles southeast of Sacramento, where San Joaquin County sheriff's officials used a backhoe to dig a 45-foot-deep pit and unearth skull fragments, bones, coats, shoes, a purse and jewelry.

"It's a gruesome sight, it really is," Deputy Les Garcia said Sunday night as searchers worked to outrace a rainstorm headed for the area.

The search is expected to continue at 7 a.m. today as investigators look for victims of Loren Herzog and Wesley Shermantine, the so-called "Speed Freak Killers" believed to have killed more than a dozen people in the 1980s and 1990s.

The discoveries began Thursday, when searchers found a skull in Calaveras County that was identified as that of Cyndi Vanderheiden, a 25-year-old Linden woman who disappeared in 1998.

Friday, at a different burial site in Calaveras County, another skull was found.

Sheriff's officials have not publicly identified that victim, but it is believed to be Chevelle "Chevy" Wheeler, a 16-year-old who disappeared in 1985.

Saturday, authorities turned their attention to the well near Linden and unearthed a skull fragment and other bones.

Garcia said investigators will not speculate on how many victims may be at the site, but Shermantine has supposedly indicated there may be as many as a dozen.

The discovery of the remains, after so many years without a trace, came about through a bizarre sequence of events involving Stockton Record reporter Scott Smith and Sacramento bounty hunter Leonard Padilla.

Shermantine has been corresponding with Smith for several years and recently provided a map and information to the reporter that authorities have been using to trace burial sites, Garcia said.

At the same time, Padilla has been encouraging Shermantine to help grieving families by pinpointing the location of the bodies. Padilla, who has tried for years to persuade Shermantine to reveal the burial sites, said Sunday night that the convicted serial killer finally agreed to, for a price.

Shermantine asked Padilla to pay his $18,000 in court- ordered restitution and also to come up with $15,000 more to provide for his child and purchase headstones for his deceased parents.

"So, for a couple (of) years we'd go back and forth and he said, 'I need the money now,' " Padilla recounted. "And I said, 'Well, give me the bodies.' "

At one point, officials discussed having Shermantine transported from San Quentin's death row to help pinpoint the burial sites, but that idea was scrapped.

Shermantine and Herzog were boyhood friends and over time each attempted to blame the other for the killings.

Herzog was convicted of three killings in 2001 and sentenced to 78 years. But an appeals court threw out the convictions on the grounds that he was coerced into talking about the killings.

He pleaded guilty to voluntary manslaughter in the Vanderheiden case and served prison time until last year, when he was paroled and moved into a trailer outside the High Desert State Prison near Susanville while authorities worked to figure out where he could be sent to live.

He killed himself last month shortly after Padilla called him and told him he needed a lawyer because Shermantine was talking.

Padilla said he believes Herzog couldn't face the possibility of returning to prison once the bodies were found.

Shermantine, who has no chance at parole because he was sentenced to death, now contends that all of the killings were done by Herzog, Padilla said.

"Ever since Herzog killed himself, it's been, 'Everything was done by Herzog,' " Padilla said.

Padilla, who thrives on publicity and is planning yet another run for mayor of Sacramento, said he has not paid out a dime yet for Shermantine's information, but that he plans to open a trust account today and explore how he can pay the restitution and other funds he promised.

The San Joaquin County sheriff has established a hotline for people to call if they have a missing-person case they believe may be related to the Herzog-Shermantine case.

People can call the hotline at (209) 468-5087 and leave their name, phone number, the name of the missing person and case number. That information also can be emailed to coldcase@sjgov.org.

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