Ashley Ellerin - Former Ashton Kutcher Girlfriend Murder Cold Case Trail

was a 22-year-old fashion student, model and's girlfriend when she was brutally stabbed to death in her Hollywood Hills home in 2001.

On the night of her murder, Kutcher stopped by to pick Ellerin up for a post-Grammy Awards party, but she didn't answer the door. The actor checked a back window and saw what he thought were red wine stains on the carpet and left. A friend discovered her body the next day.

Kutcher, who married actress Demi Moore in 2005, was never a suspect in the case.

In a new development in the unsolved murder, DNA evidence has linked Michael Thomas Gargiulo, a 32-year-old air conditioning repairman being held on suspicion of the murder of a Santa Monica woman in April.

Police said the DNA match also links Gargiulo to the fatal stabbing of a Monterey Park woman in 2005 and the 1993 killing of high school classmate Tricia Pacaccio in the Chicago suburb of Glenview, where Gargiulo lived at the time.

Gargiulo was being held in lieu of $1.1 million bail on attempted murder and burglary charges stemming from the April 28 stabbing of a Santa Monica woman in her home. Detectives matched a DNA sample taken from blood at the crime scene to Gargiulo. Further database cross-referencing found that Gargiulio's DNA matched genetic evidence in the three killings.

Kutcher's agent, Stephanie Simon, said the actor had no comment.

View photo of Ashley Ellerin and Ashton Kutcher below.