Diana Vicari

Status:

Open

Jurisdiction:

Tucson Police Department (AZ)

Offense Location:

Tucson, Arizona

Summary:

Diana Vicari, 19-year-old Pima Community College student working two part-time jobs, was last seen near the Tucson Convention Center on October 22, 1992 for a concert. Her severed arms were found in a dumpster in downtown Tucson on October 24, 1992. A man was found guilty of her murder in 1999 after a two-week trial, but the conviction was overturned in 2003 by the Arizona Supreme Court. To date, no other remains belonging to Vicari have been recovered.

Vital Statistics

Circumstances of Offense:

Diana was last seen by her family on October 22, 1992, after attending a Pima Community College drama class at Palo Verde High School and driving a classmate home; she was then seen in the parking lot of the Tucson Convention Center. On October 22, 1992, there was a concert called 'Moshtoberfest' at the Tucson Convention Center. Vicari was last seen alive after the concert, just past midnight, driving in the parking lot of the TCC and asking other concert-goers about a house party. Her car was found at the 1200 block of West La Osa Street in the Flowing Wells neighborhood, close to where a large party was held that night, but witnesses told authorities she hadn't attended. Her severed arms were discovered two days after the concert, in a large, rusted trash bin on North Ferro Avenue, an alleyway close to the Downtown intersection of East Sixth Street and North Sixth Avenue. The murder of Diana Vicari occurred between October 22 and October 24, 1992.

Additional Details:

Police began to suspect Lemuel Prion, who had a criminal record and had often talked about sexually assaulting or hurting women; in 1995, newspapers printed a photo of Prion, naming him as the prime suspect in the Vicari murder. On January 28, 1999, Prion was convicted of the first-degree murder of Vicari and the kidnapping and aggravated assault of Armentha, and sentenced to death. In August 2002, the Arizona Supreme Court unanimously overturned the conviction, ruling that the trial court should not have heard Vicari's and Armentha's cases at the same time, and should have allowed the defense to present evidence indicating that another suspect had committed the murder. According to the Supreme Court, 'There was no physical evidence identifying Prion as her killer,' and the trial court abused its discretion in not allowing the defense to submit evidence that a third party, John Mazure, was the actual killer. Mazure, who was also a suspect in the murder, was known to have a violent temper, saw Vicari the night of her disappearance, concealed information from the police when they questioned him, and 'appeared at work the next morning after Vicari's disappearance so disheveled and disoriented that he was fired.' On March 14, 2003, the Pima County Attorney's Office dismissed all charges against Prion, and he was returned to Utah to serve out the remainder of his previous sentence. While most of Diana's immediate family has since passed, her sister said in 2002 she was convinced Prion was the man guilty in her sister's murder; 13 News has also learned Prion has since died.

Case Last Updated:

Nov 06, 2026