(CBS/AP) BELLEVUE, Wash. - Police say the mother of missing Washington State toddler Sky Metalwala didn't run out of gas on the day the boy disappeared, as she had previously told investigators.
Julia Biryukova told police her 2-year-old son vanished Sunday in Bellevue, Wash. when she left him sleeping alone in her unlocked car after it ran out of gas. She said she and her 4-year-old daughter went to get gas and when they returned an hour later, the boy was gone.
But Investigators found that there was enough gas in the car to run a considerable distance, Bellevue police Maj. Mike Johnson said Wednesday. Police have not yet ruled out some other mechanical problem with the car.
Johnson says Biryukova's story has become less and less plausible as police have tried and failed to find any evidence that supports the facts as she presented them.
Johnson revealed that Biryukova said she was taking the boy to a hospital because he didn't feel well -- even though she left her purse, wallet and identification at home. It wasn't clear how she expected to get gas for the car or have her son treated without the items, he said.
He emphasized, however, that Biryukova remains cooperative in other ways, by answering every police question through her attorney, driving police along the route she drove and then walked, and allowing complete access to her home and car.
Sky's disappearance came amid a bitter divorce and custody fight between Biryukova and the boy's father, Solomon Metalwala. During a tough mediation session that lasted about 12 hours last week, the parties reached a tentative agreement that would allow Metalwala to have some visitation with Sky and his older sister.
But two days later -- and two days before she reported her son missing -- Biryukova decided to pull out of the agreement, Metalwala's divorce attorney, D. Michael Tomkins, said Wednesday. In a letter sent by her attorney, Biryukova insisted that everyone at the mediation session had been against her and the settlement was unfair, Tomkins said.
Papers filed in the divorce say that Biryukova suffered from "severe" obsessive-compulsive disorder. Metalwala wrote in a declaration that she would frequently go on 10-hour cleaning binges during which she wouldn't even feed the children, but a doctor reported that her diagnosis did not interfere with her ability to care for the kids.
Investigators on Wednesday were focusing on processing the car for forensic evidence. They also were giving voluntary polygraph exams to the boy's father and several of his relatives and taking DNA samples to match with DNA evidence found at Biryukova's apartment.
Johnson said the tenor of the investigation has changed because they've run out of options for searching for the child. He denied media reports that police were searching landfills or garbage transfer stations, but did not rule out that possibility if evidence indicates they should go there.
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