An infant girl who died of a high body temperature might have been put in a microwave, and her mother has been charged in the death, authorities said Tuesday.

The month-old baby was dead when her mother, China Arnold, 26, brought her to a hospital Aug. 30 last year, police said.

"We have reason to believe and scientific evidence to support that a microwave oven might have been involved in the death of this child," said Ken Betz, director of the Montgomery County coroner's office.

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Arnold, who was arrested at her home Monday on a charge of aggravated murder, had nothing to do with her the death of her daughter, Paris Talley, defense attorney Jon Paul Rion said. The mother was stunned when investigators told her that a microwave might have been involved, he said.

"China — as a mother and a person — was horrified that such an act could occur," Rion said. "She's in a state of shock that anyone could have done this to her child. She is completely innocent."

Arnold and the child's father went out for a short time and left the child with a baby sitter the night before the child was taken to the hospital, Rion said.

"China didn't sense anything out of the ordinary until the morning," Rion said.

The couple woke up about 5:30 or 6 a.m., and the father picked up the child and noticed that something was wrong. Rion said the child was unconscious, and the parents immediately rushed to Children's Medical Center.

Rion declined to say what the couple told hospital officials.

"We're very curious as to why now — some year-and-a-half later — police are now looking at China," he said.

The microwave was taken as evidence, police Sgt. Gary White said.

"The microwave oven is definitely part of the investigation," he said.

The death was ruled a homicide caused by hyperthermia, or high body temperature, because of burns. But the burns the child suffered were not external ones as there would have been with scalding water, Betz said.

Betz said the case is a difficult one.

"There is not a lot of scientific research and data on the effect of microwaves on human beings," he said.

Arnold had been arrested initially and later released.

Greg Flannagan, a spokesman for the county prosecutor's office, said there was a lengthy investigation before prosecutors determined there was enough probable cause to issue an arrest warrant.

Arnold, who was being held in the Montgomery County jail, plans to plead not guilty and will request a hearing to contest the allegations, Rion said.

Arnold had attended a community college and was working at a mini-market. Rion said she has three other children.

"She loves her children very much," Rion said. "She's been wanting to try to understand what happened. The last thing in her mind is that she herself would ever be charged."

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