UPDATED 04/26/11 11:25 p.m.

CALUMET CITY, Ill. (STMW) — A pregnant woman found strangled in a forest preserve near Calumet City on Sunday is a missing 18-year-old Alsip woman, who was last seen a day prior at a restaurant with a friend, authorities said on Tuesday.

The South Suburban Major Crimes Task Force now is investigating the death of Rosemary “Rosie” Newman, 18, who was strangled to death, said Tim McCarthy, the Orland Park police chief who heads the task force. She was nine months pregnant, he said.

No one is in custody yet, though police are questioning a number of people, he said.

Newman’s body was found sometime between 7:30 a.m. and 8 a.m. Sunday by a man who was walking his dog in a Cook County Forest Preserve, Cook County Sheriff’s office spokesman Steve Patterson said.

The woman was discovered near Freeland Avenue and Warren Street near Calumet City, according to the Cook County Medical Examiner’s office. That location is on the north border of Calumet Park.

An autopsy on Monday found Newman was strangled and her death was ruled a homicide, the medical examiner’s office said.

Newman was last seen at a south suburban restaurant with a friend Saturday night. Her family reported her missing after she failed to return home, Patterson said.

The sheriff’s office, with the help of other members of the South Suburban Major Crimes Task Force, is now pursuing several leads in the case, including collecting evidence and conducting interviews, Patterson said.

The case remained an open investigation on Tuesday evening.

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