Updated

Child-sized human remains uncovered in a basement freezer were those of two girls and have been there for months, their adoptive mother told investigators. Authorities said Monday they believe she is responsible for their deaths.

Sheriff's deputies were investigating an abuse complaint regarding a third, surviving child Saturday when they discovered the remains encased in ice. The mother told investigators that they had been in her southern Maryland home's freezer for at least seven months, and police said they are considering the case a homicide.

"We have reason to believe that's the two children in the freezer," said Lt. Bobby Jones of Calvert County Sheriff's Office. "We believe that the mother, who adopted the two children, is responsible for it."

Autopsies would need to be completed before authorities know for sure whether it is the girls, who would be 9 and 11. Deputies made the gruesome find in Lusby, about 50 miles southeast of Washington, D.C. They were at the home with a search warrant to investigate what happened to a runaway 7-year-old girl who was found wandering the neighborhood, injured and hungry in a blood- and feces-soaked nightshirt.

The girl's mother, 43-year-old Renee Bowman, has been arrested, and a judge has ordered her held without bond. She is charged with first-degree child abuse in the beating of the 7-year-old.

"I asked if she was OK. She said no," said neighbor Phillip Garrett, who found the girl walking down the street. "She said, 'My mother beats me to death all the time."'

She escaped from a locked bedroom by jumping out a second-story window, and Bowman admitted beating her with a "hard-heeled shoe," officials said.

Bowman told detectives that she brought the remains of her other daughters with her when she moved in February from Rockville, about 60 miles away. Montgomery County Police said they are investigating whether the deaths took place in Rockville and that detectives are trying to pin down when the older girls were last seen alive. Bowman has not been charged in the deaths.

The medical examiner's office in Baltimore planned to examine the freezer and its contents, but it was unclear how long it would take for the remains to thaw sufficiently.

Bowman was a foster mother to all three before adopting them in the District of Columbia, officials said at a news conference.

According to charging documents in Calvert County, the youngest girl went door-to-door looking for help Friday night.

The girl had open sores and lesions on her buttocks and lower thighs, marks on her neck made by a cord, rope or other item and bruises on her hands and lips, police said.

The girl is in a hospital. The Maryland Department of Human Resources plans to petition the court Tuesday to gain custody, said Nancy Lineman, an agency spokeswoman.

Garrett, 21, who lives two houses down from Bowman, said he brought the girl to a neighbor's house, called 911 and ordered her a pizza. She indicated she had last eaten on Tuesday when her father was at the home, said Garrett, who realized he had met her mother once and described her as "frazzled."

"She didn't seem like all her pieces were there," Garrett said.

Later Friday, authorities went to Bowman's modest, single-story house in the secluded, heavily wooded subdivision but nobody was home. Bowman showed up later at the sheriff's office and said she had locked her daughter in the child's bedroom.

She told the deputy who interviewed her about the 7-year-old's abuse "that she knew what she did was wrong," according to the charging documents. "She advised she (Bowman) was out of control and needed help."

Sheriff Mike Evans said the surviving girl was never enrolled in Calvert County Schools and that no trouble had ever been reported at the house. Bowman's only contact with the sheriff's department since she arrived was a traffic stop.

Lineman said her agency had no records to indicate the involvement of child-protective services with Bowman's family, but a review of statewide records has been ordered.

Evans said Bowman had a boyfriend who was cooperating with investigators. The boyfriend was a potential witness, but Evans would not comment on whether he was a suspect. He said the man did not live with Bowman and was not a father to her children.

No attorney had entered an appearance on Bowman's behalf Monday afternoon.

Bowman adopted the oldest girl in July 2001, D.C. officials said. Three years later, she adopted the girl who would now be 9 and her 7-year-old sister. She is not biologically related to them.

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