Wesley Shermantine of notorious 'Speed Freak Killers' dies in prison at 60, officials say

SACRAMENTO, Calif. (KGO) -- One of the notorious "Speed Freak Killers" has died in prison.

Officials announced Wesley Shermantine's death on Friday, a day after he died. He was 60 years old. The cause has not been released.

Shermantine was on death row at a state prison outside of Sacramento at the time of his death.

Shermantine, along with childhood friend Loren Herzog, was suspected of dozens of killings in the San Joaquin County area that started in the 1980s and ended with their arrest in 1999.

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Shermantine was condemned to death row in 2001 in Santa Clara County.

In 2012, investigators excavated a site near Linden to look for remains but came up empty.

The duo was also looked at as possibly being behind the disappearance of nine-year-old Michaela Garecht of Oakland but the investigation led to the arrest of 59-year-old David Misch in 2020.

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They were nicknamed the "Speed Freak Killers" because they were often high on methamphetamine.

Herzog struck a plea deal and was released from prison in 2010. He died by suicide in 2012.