California ? Spooky rumors have persisted for decades that there might be clandestine graves at a secluded ranch used as a hideout by the Charles Manson clan after a 1969 killing spree.

Today, Inyo County Sheriff’s investigators and scientists packing portable ground-penetrating radar, magnetometers and shovels will convoy to the Barker Ranch near Panamint Springs on a mission to confirm or end such speculation.

The search is expected to continue through Thursday.

An imprisoned member of the so-called Manson family suggested that bodies were buried at the Barker Ranch. Preliminary tests of soil samples and with search dogs have yielded mixed results.