Investigators are trying to determine if carbon monoxide from a malfunctioning pool heater led to the death of four people at a Yerington motel on Easter Sunday.
"Late last night we found some more findings that really pointed to the CO," said Fire Chief Scott Huntley with the Mason Valley Fire Protection District.
Phillip Doll Jr., 27, of Yerington, was found dead Sunday in room 242 of the Casino West Motel. His friends Juan Pablo Chavez, 28; Veronica Chavez, 20, and Donna Vega-Robles, 30, all from Contra Costa County, Calif., were found unconscious and later died at the hospital.
On Monday night, investigators tried to "simulate the conditions in the room" during the time surrounding the deaths by starting the pool's heater and closing the windows and doors of the room. In protective gear, they entered the room to test air quality and found elevated levels of carbon monoxide, Huntley said.
He said the room sits directly above a ground-level room in which the outdoor pool's water filtration and heating systems are housed.
The pool had been closed through the winter and the heating system had recently been turned on again, he said.
"But until the toxicology results are back from the autopsies, we won't really know what killed them," Huntley said.
On Sunday, a tenant in a room below complained to maintenance of a water leak above. When the worker went to investigate, he found Veronica Chavez fully clothed and unconscious in the bathtub with the water still running and her husband, Juan Pablo Chavez, on the bathroom floor. Vega-Robles was unconscious in the bedroom and Doll was pronounced dead at the scene.
Doll's mother, Suzan Doll, said her son's friends had come to visit for Easter. She and her husband expected them for dinner at 3:30 p.m.
The Nevada Department of Public Safety Investigations Division and the Forensic Investigations Unit from the Washoe County Sheriff's Office are assisting in the investigation.
• Contact reporter F.T. Norton at ftnorton@nevadaappeal.com or 881-1213.