(BELLEVUE, Wash.) -- Julia Biryukova, the mother of the 2-year-old toddler who went missing Sunday in Bellevue, Wash., has refused to take a lie detector test.
Police made the announcement Tuesday as detectives began focusing their search on the area surrounding her Redmond apartment.
Biryukova told police she was driving her two children to Overlake Hospital Medical Center in Bellevue because her younger child, Sky Metalwala, wasn't feeling well. She said she ran out of gas on 112th Avenue, a two-way street that borders Interstate 520, so she and her 4-year-old daughter trekked about a mile to a nearby gas station, Northtowne Chevron Service, leaving Sky in the car.
Police said she then called a friend, who took her to her car about an hour later. But when they returned to the two-door silver Acura, Biryukova said, the boy was gone.
"We continue to invite her to take a polygraph and as of yet she has not taken one," said Bellevue police spokeswoman Carla Iafrate, adding that Sky's mother did allow police to search her car and the inside of her home.
Biryukova is allegedly in the middle of a difficult divorce with her husband, Solomon Metalwala. He hasn't seen either of his two children in "several months," police said. Metalwala took a polygraph test Monday, but the results were inconclusive, something Iafrate said is "not unusual." He volunteered to take another test Tuesday.
Clay Terry, one of the attorneys representing Metalwala, was not immediately available for comment. But he told ABC News affiliate KOMO that his client is "exhausted" and hadn't slept much since his son disappeared.
The father of two has kept out of the spotlight, making one brief, soft-spoken public statement to reporters Monday outside his lawyer's office, saying, "Please just return him back, like I just said to the police officers, the hospitals and the fire department. Please."
Police have emphasized they aren't naming any suspects yet, but they do suspect "foul play."
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