PITTSBURGH — A woman was fed vegetable oil, spices, detergent, urine and medications and forced to write a suicide note before she was stabbed to death, wrapped in plastic and put in a garbage can and dumped in a school parking lot, police said Friday.

Six people were charged with criminal homicide, kidnapping and related charges in the death of Jennifer Daugherty, whose body was found Thursday at Greensburg Salem Middle School, about 30 miles east of Pittsburgh.

She had been missing since Monday and she was identified by family, according to police. Her age and address were not immediately available. An afternoon news conference was scheduled.

Charged are: Robert Loren Masters Jr., 36; Ricky Smyrnes, 23; Melvin Knight, 20, Amber Meidinger, 20, all of Greensburg; a 17-year-old Greensburg teenage girl, and Peggy Darlene Miller, 27, OF Mount Pleasant Township. All were being held without bond in the Westmoreland County Prison.

According to an affidavit of probable cause, Knight admitted stabbing Daugherty in the chest, side and neck, and he and Smyrnes carried her body to the parking lot. All six defendants admitted their involvement and implicated others, according to police.

Daugherty's hair was shaved and she was bound with Christmas decorations and clothing.

A neighbor in a first-floor apartment reported hearing a "tussle upstairs and a 'heavy bam,' "as though a body fell, causing the ceiling to shake before it went quiet on Wednesday night, the affidavit said.

A man found Daugherty's body Thursday morning when he saw the plastic garbage can partially beneath his truck.