WASHINGTON (CNN) -- A mother suspected of killing her four children, whose decomposing bodies were found in her home, told police they were possessed by demons, according to court records.

Banita Jacks, 33, is charged with three counts of felony murder and one count of first-degree murder while armed.

The victims, who range in age from 5 to 17 years, are thought to be her daughters. Their bodies were found when U.S. marshals served an eviction notice at Jacks' apartment in southeast Washington, D.C.

Court documents say Jacks identified the victims as her daughters Brittany Jacks, 17; Tatianna Jacks, 11; N'kiah Fogle, 6; and Aja Fogle, 5.

Earlier Thursday, Mayor Adrian Fenty said the bodies' decomposition has hindered their identification, although they were believed to be Jacks' children.

Marie Pierre-Louis, Washington's chief medical examiner, said all four of the girls had been dead for at least 15 days.

Jacks is being held without bail. Her next court appearance is scheduled for February 11. If convicted, she could receive a maximum sentence of life in prison.

Jacks told police that her daughters were possessed by demons and that each died in her sleep during a seven- to 10-day period, court documents said. Aja died first, she told police, then N'kiah, Tatianna and Brittany.

"She said that as the first three younger children died, she placed them side by side in the room in which they died," according to court documents.

She reported that all the deaths occurred sometime before the electricity in her house was disconnected, which records show was September 5, 2007, documents said.

Jacks said she never tried to call authorities to remove the bodies "because she didn't trust either agency and because she thought if she notified emergency personnel, that would cause her more problems," the documents said.

She also said she had not fed her daughters food "for a substantial period of time prior to their deaths."

No one besides herself or the children had been in the home since May 2007, Jacks said.

Pierre-Louis ruled the deaths homicides, according to a court document. Watch Pierre-Louis describe the condition of the bodies »

Preliminary findings are that Brittany was stabbed to death and that Aja died from blunt-force impact to the back of her head and possible ligature strangulation.

Both Tatianna and N'kiah also had "apparent ligature evidence" on their necks that was "somewhat more defined than that noted on Aja Fogle's neck," court documents said.

However, the documents said, further tests are needed to confirm the causes of the deaths.

All four children were wearing white T-shirts and were discovered in unfurnished bedrooms -- three in one and a fourth in another, the documents said.

"What appeared to be a metal steak knife" was found next to the fourth. Also, the fourth body was found in a bedroom with hardwood floors, and a T-shirt with duct tape was found at the bottom of the bedroom door, filling the gap between the floor and the bottom of the door when it was closed.

A witness told police they saw Jacks treat Brittany differently from her other children, sometimes withholding food from her while feeding the others, court documents said.

In addition, the witness said Jacks once drove Brittany to Jacks' mother's home in Waldorf, Maryland, and left her there. Jacks' mother was not home, the witness said, and Brittany was left on the porch unattended for more than 10 hours.

City officials are trying to determine how the children could have been dead for at least two weeks without anyone noticing their absence. Fenty said the city had determined that Jacks' children were "in and out of the public school system" and that the child welfare caseworkers and the metropolitan police had each had at least "one contact" with the family. Watch Fenty explain how a "routine" eviction became a death investigation »

"There may be other contacts with the government ... in the case of the Jacks family," he said.

He did not divulge further details.

"Somebody should have known that these young people were not in school or someplace," Councilman Marion Barry said Wednesday. The former Washington mayor represents the ward in which the bodies were found. E-mail to a friend

CNN's Larry Lazo contributed to this report.