ALAMEDA COUNTY -- Authorities Friday afternoon are investigating a double homicide in an unincorporated part of Alameda County near Pleasanton, according to the Alameda County Sheriff's Office.

Two bodies, a man and a woman, have been located in a residence on Castlewood Drive near the entrance of the Castlewood Country Club, said Sgt. J.D. Nelson. Investigators were in the area at 3:30 p.m., however the time the incident was first reported was not immediately available.

A relative who had not heard from one of the victims contacted authorities, triggering an investigation, Nelson said.

A coroner will not be able to identify the victims until the scene has been fully processed for trace evidence.

"They come when we have cleared most of the scene," Nelson explained.