UPDATE: Sunday, June 8, 2014 at 11:49 a.m.
The subjects were identified by the San Luis Obispo Sheriff's Department as Robert Berg 82 years old of Paso Robles and John Warren, 66 years old of Paso Robles.
Neighbors describe the men as very knowledgeable pilots who loved the Paso Robles area, and were well-respected in the community.
The San Luis Obispo County Fire Department reported Saturday morning that there were two fatalities connected to a single engine aircraft crash near Fairhills Road and Vineyard Drive near Templeton, on the rural west side of the Paso Robles wine region.
The San Luis Obispo County Sheriff's Department confirmed that two men were killed in the crash. Next of kin still needs to be notified, so the identities of the victims was not immediately released.
"Witnesses reported seeing the plane take off and then a short time later start to bank to the right," said Tony Cipolla, the sheriff's department spokesperson. "It continued this circular pattern until it spiraled to the ground."
Residents in the region tell KCBX that a helicopter has been hovering over the immediate area. An airstrip is located nearby, according to one neighbor, on the ranch previously owned by actor Josh Brolin.
There was no fire associated with the crash and neighbors said they were surprised they didn't hear anything.
The National Transportation Safety Board (NTSB) and the Federal Aviation Administration (FAA) are investigating.