The mother in western Japan arrested after her two daughters died of heatstroke left them in a parked car while she went to at least three bars with a male friend until the early hours, investigative sources said Saturday.

Maria Takeuchi, 26, was arrested Friday for allegedly leaving her daughters -- Mayuri, 6, and Yurie, 3 -- in a car in Takamatsu, Kagawa Prefecture, for over 15 hours through early Thursday afternoon, when the children were found unresponsive. They were later pronounced dead at a hospital.

While the mother said at the scene that she left the car for about two hours to go to a restroom, footage from surveillance cameras and witness accounts indicate that she left the children around 9 p.m. Wednesday and likely went to at least three bars until the following morning, the sources said.

She was sent to prosecutors on Saturday.

Autopsies found that the girls died of heatstroke, police said. The temperature rose to as high as 37.6 C in Takamatsu on Thursday, a record for the city in September.

==Kyodo

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