LINDEN (CBS) - Crews from the San Joaquin County Sheriff's office and FBI are back in Linden searching for evidence connected to the Speed Freak Killers.
Evidence Recovery Teams from the Sheriff's Department and FBI are digging on a parcel of private property on Drais Road just outside of Linden.
Wesley Shermantine and Loren Herzog, known as the Speed Freak Killers, went on a methamphetamine-fueled killing in the 1980s and 1990s. Some people believe they could be responsible for as many as 25 unsolved murders.
"We will continue working with the Federal Bureau of Investigation (FBI) and the California Department of Justice (DOJ), Bureau of Forensic Services, utilizing what-ever resources necessary in the recovery and identification of missing loved ones, said Sheriff Steve Moore, San Joaquin County Sheriff. "We all have a common goal, bringing them home to their families."
Earlier this year, authorities found the remains of two known victims and two suspected victims of the Speed Freak Killers during a series of digs in and around Linden at sites known to be associated with Shermantine and Herzog.
"The intent of all agencies involved is to locate and identify victims so they may be returned to the families who have been searching for them for many years to bring closure and peace. Unfortunately, the credibility of investigative resources is eroding and the hope of finding additional victims is beginning to fade," said Herb Brown, Special Agent in Charge of the Sacramento Division of the Federal Bureau of Investigation.
Shermantine has been on death row since he was convicted in 2001 of killing four people. He has been talking with officials and media over the last several months, offering to give details about burial sites in return for money.
Herzog was found guilty of three murders but his murder convictions were later overturned on appeal. He was sentenced to 14 years and released in 2010. He committed suicide outside High Desert State Prison in Susanville earlier this year, where he was living in a mobile home after his release.
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