When the blaze broke out on Friday, only eight of the children were in the house. Yuan had taken the older ones to school or left them in the care of other people, Wu Changsheng, deputy chief of the county, said at a news conference on Saturday. The unhurt children have been sent to a welfare home in Kaifeng, which administers Lankao.
The fire swept through the home, killing four children at the scene. The other three victims lost their lives on the way to hospital.
A 10-year-old injured child remains in intensive care.
Two days after the fire, Yuan, 48, was lying in bed in a hospital in Lankao, her eyes shut.
"I received a phone call from publicity officials around 10 pm on Saturday and was told that my mom was sick," said Du Ming, Yuan's younger son. "So my elder brother and I rushed to the hotel where my mom was staying and took her to the hospital.
"My mom hasn't eaten a meal since this happened. Her heart attack was the result of anxiety."
Before Yuan had the attack, local authorities had been holding her in a hotel room for questioning, her wheareabouts unknown to her family, according to Xinhua News Agency.
The cause of the fire is still under investigation.
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