Cyanide--but no suicide note--was inside Ian Stuart Spiro's vehicle when the British businessman, who is the prime suspect in the deaths of his three children and wife, was found dead in the Anza-Borrego Desert, the San Diego County Sheriff's Department confirmed Thursday.
The actual cause of Spiro's death remains under investigation, pending completion of toxicology studies by the San Diego County medical examiner's office.
The 46-year-old Spiro, a purported British spy, is suspected of the execution-style killings nearly two weeks ago of his wife, Gail, 40, and their three children--Sara, 16; Adam, 14, and Dina, 11. Each was shot in the head and found in separate bedrooms in the Rancho Santa Fe home they rented on Avenida Maravillas.
Authorities have yet to suggest any motives for the killings. Despite rampant speculation in the British press that Spiro and his family may have been killed by foreign agents, acquaintances of the family say Spiro may have fallen on tough financial times. A note was found on a door of the home asking why a $5,000 rent payment was tardy.
Spiro's wife and children are believed to have been killed sometime between Sunday night, Nov. 1, and Monday morning, Nov. 2, although the death scene wasn't discovered until Nov. 5 after neighbors called authorities because they hadn't seen the family for several days.
Spiro's body was found Sunday afternoon in the driver's seat of his locked Ford Explorer by hikers in the Anza-Borrego Desert, about 75 miles northeast of San Diego. The vehicle, with its key in the ignition, was about a mile north of route S-22 inside the state park's boundaries.
Lt. John Tenwolde of the sheriff's homicide detail said Thursday that detectives completed their search of Spiro's vehicle "and found several grams of granular sodium cyanide in a bag between the front seats."
Cyanide, which can be obtained through chemical supply houses, is a highly toxic chemical that can cause death within minutes of ingestion.
"Also found were a cup and two water bottles, one of which was full and the other empty," Tenwolde said. "No weapons were in the vehicle nor were there any communications regarding the death of Ian Spiro or his family."
Investigators are also combing through evidence found inside the Rancho Santa Fe rental home.