According to a press release from the department, the change in the investigation is based on surveillance video and current known evidence, "unless additional information or evidence comes to light."
The man, described as a local transient, was detained as a person of interest in regards to the case on May 4 and arrested for an unrelated charge. He was later released.
Susan Leeds, 66, was found stabbed to death inside her car at the Promenade on the Peninsula shopping center parking lot on May 3. She was initially located by other shoppers. By the time help arrived, she was already dead, stabbed several times in her upper body.
A motive behind the killing is not known.
The victim was captured on video surveillance prior to the attack, and investigators provided a still capture of the footage in an effort to help potential witnesses who may have seen Leeds on the day of the incident.
She was approximately 5 feet 2 inches, about 140 pounds and wearing a blue short-sleeved shirt, black workout-type pants and pink shoes with white soles.
Investigators encourage anyone who saw anything out of the ordinary, suspicious activity or persons, inside of the parking structure on May 3 between the hours of 10:30 a.m. and 12:30 p.m. to call the Sheriff's Homicide Bureau at 323-890-5500.