The gunman behind the killings of a Simi Valley doctor and his wife turned out to be the victims’ son, Simi Valley and San Bernardino County officials confirmed Tuesday.

After gunshots were heard on Hawks Bill Place near Sycamore Ridge Street at around 12 noon Sunday, neighbors said they saw a black sedan with out-of-state license plates as well as a man in his 30s in dark clothing and a hat, the Simi Valley Police Department said in a statement.

Police said Dr. Eric Cordes and his wife, Vicki, were found in the garage of their home with gunshot wounds. They were taken to a hospital but died from their injuries. 

Based on witness accounts, detectives then tracked down the black car, using a camera system that reads license plates, and learned the vehicle, a Honda Civic, was registered to 37-year-old Keith Cordes, the son of victim Eric Cordes. Vicki Cordes, another victim, was the stepmother, police said.

Police were also able to follow the car’s movement and determined that it ended up at a parking lot in Chino.

As authorities in Chino and Simi Valley began to collaborate, they learned of a vehicle fire and possible suicide at the same Chino parking lot, involving the black sedan registered to Keith Cordes. 

Investigators concluded, more than two hours after the shooting deaths of the Simi Valley couple, the son set the car on fire before fatally shooting himself. 

The San Bernardino County Medical Examiner’s Office also confirmed the deceased person found at the Chino parking lot was indeed Keith Cordes, ruling that he died from self-inflicted gunshot wounds. 

“While additional forensic testing is pending, Detectives believe the firearm recovered from Keith’s suicide is the same weapon used in the homicides of Eric and Vicki Cordes,” Simi Valley police said. 

Detectives said they are continuing to investigate the motive behind the double murder.

A Simi valley hospital also identified the married couple as Dr. Eric Cordes and his wife, Vicki.

“The Adventist Health Simi Valley community is heartbroken by the tragic deaths of our longtime colleague, Dr. Eric Cordes, and his wife, Vicki. Dr. Cordes was a highly respected, board-certified radiologist and beloved physician who served this community with compassion and excellence for nearly 30 years. Our hearts are with his family, friends, and all who had the privilege of working alongside him as we grieve this shocking loss,” wrote Adventist Health Simi Valley in a statement to NBCLA.