A 26-year-old mother in Takamatsu in western Japan was arrested Friday for allegedly leaving her two small daughters in a parked car at night while she went bar-hopping and causing their deaths, police said.

Both kindergarteners, the girls -- Mayuri, 6, and Yurie, 3 -- were found unresponsive Thursday afternoon and declared dead at a hospital. The suspect, Maria Takeuchi, was drinking until dawn, according to the police.

The girls are suspected to have suffered heatstroke, they said. The temperature rose as high as 37.6 C Thursday in Takamatsu, Kagawa Prefecture, a record for September.

Takeuchi allegedly left them in a passenger car at a parking lot in Takamatsu from around 9 p.m. Wednesday, resulting in their deaths, the police said, adding she is remaining silent regarding the allegations.

After drinking until dawn Thursday, she moved the car and found the girls limp on the rear seat. As she did not call for an ambulance until the afternoon, the police are investigating what she did during the intervening time.

==Kyodo

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