Illinois police searched a nearby park Friday for the three missing children of a murdered pregnant woman whose fetus was cut from her womb.

Police identified the victim as 23-year-old Jimella Tunstall, and said they were questioning the woman's cousin, a 26-year-old woman. Both women lived in East St. Louis, reports said.

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Police said the woman in custody was a "person of interest" in the case, but would not say whether any charges were pending.

Dozens of searchers scoured the densely wooded Frank Holten State Park in East St. Louis looking for the dead woman's three children, identified as: Demond Tunstall, 7; Ivan Tunstall, 3; and Jinella Tunstall, 2. A boat also searched the shoreline of a lake by the park. The children have not been seen since Monday, but police said they were not alerted to their disappearance until after their mother's body was found late Thursday night, Fox TV station KTVI reported.

Their disappearance has been reported to the National Center for Missing and Exploited Children.

"We're hoping to recover the children alive," said East St. Louis Police Captain Craig Koehler told reporters Friday afternoon, adding that police have searched area parks — including bodies of water — for the children.

"The focus of our investigation at this point is trying to locate these children," Koehler added.

"We would ask that if anyone has information about the whereabouts of these children that they would contact our command post," even if tipsters wish to remain anonymous, he added.

A funeral for a baby a woman claimed was hers and had been stillborn was held Thursday, East St. Louis Police Chief James Mister told the Belleville News-Democrat.

The newspaper reported the woman later told her boyfriend she had killed a woman and stolen the baby.

An autopsy was scheduled for Friday to determine if the baby was removed from Tunstall's womb, Mister said.

St. Louis TV stations reported that the woman being questioned went to Touchette Regional Hospital in Centreville, Ill., on Friday, Sept. 15. While at the hospital, police said the woman told them she went into labor after being raped, and that the rapist delivered the child, who was stillborn.

Police believe that child may actually have been the child cut from the womb of the victim, KTVI reported.

St. Clair County State's Attorney's Robert Haida said no charges had been filed by midday Friday.

"We're not rushing to judgment," he said. "We are taking our time and waiting on reports from investigators."

None of the family members — including the father of the kids — are considered suspects, police said.

Haida called it "a very tragic case," but would not comment further.

The East St. Louis case is the second recent case in the St. Louis area involving babies.

Shannon Torrez, 36, of Lonedell, Mo., is accused of slashing a young mother's throat and kidnapping her baby on Sept. 15. The baby was returned unharmed Tuesday, the same day Torrez was arrested.

Also in Missouri, Lisa Montgomery will stand trial April 30 in the abduction of an unborn girl taken from the womb of Bobbie Jo Stinnett at her Skidmore, Mo., home in December 2004. The baby survived.

The Associated Press contributed to this report.