CASTRO VALLEY (CBS SF) — Authorities confirmed Wednesday afternoon that the two bodies discovered inside a guest house in Castro Valley suffered from gunshot wounds, authorities said.

The Alameda County Sheriff’s Office said deputies responded to the 20500 block of Forest Avenue at around 10:15 a.m. Wednesday to do a welfare check after a relative called the office and stated they had not heard from their family member in several days.

READ MORE: UPDATE: Atmospheric River Drenches Northern California, Setting Some Rainfall Records

Deputies arrived at the home and received no response. They walked down the driveway to the rear of the property where they saw a detached guest house.

Deputies found two dead bodies — a male and a female — inside the guest house, sheriff’s Sgt. Ray Kelly said.

Authorities said the victims died from suspected gunshot wounds. The two victims appeared to have been deceased for several days and there were obvious signs of foul play, according to the sheriff’s department.

READ MORE: UPDATE: Streets Flood in San Rafael, Mill Valley as Wild Storm Lashes Bay Area

The crime scene and condition of the victims have made it difficult to determine the exact circumstances of the deaths, according to Kelly. In an abundance of caution, detectives are treating the investigation as a double murder.

An autopsy and further crime scene analysis may change this circumstance. Authorities said they will provide an update once that information is known.

Currently, authorities are not naming the male and female victims pending proper identification and notification of next of kin by the coroner.

MORE NEWS: Stephen Curry Reaches 5,000 Assists, Warriors Beat Kings 119-107

Anyone with information is urged to call ACSO Investigations at 510 667-3636. Information can be reported anonymously.