Police were not able to recover fingerprints or physical evidence from the fires because it was destroyed.
Investigators also looked into previous arson arrests and individuals listed in California Department of Justice’s arson registry, but that search came up empty, Lorenz said.
Police cadets went door-to-door last month and handed out fliers to residents, asking them to report any suspicious activity.
Glendale Crime Stoppers, a local volunteer organization, even offered a $1,000 reward for any information that leads to an arrest.
“We just need residents to be vigilant and call us,” Lorenz said.
Police have arrested several arsonists over the years, but none was more prolific than John Orr, a former Glendale fire captain and arson investigator.
Between the 1980s and early 1990s, a series of fires that devastated Southern California left investigators stumped because they had no leads in finding the person responsible for them.
Orr might not have been caught if it wasn’t for a fingerprint, which was found on an incendiary device at the scene of a fire that destroyed a home-center store in South Pasadena in 1984 and killed four people, including a 2-year-old boy.
The fingerprint was eventually matched to Orr, who was then the subject of a surveillance investigation.
At the time, Orr had penned a manuscript, which was later published in a book titled “Points of Origin,” detailing the story of a firefighter turned serial arsonist as well as fires that were similar to actual events.
Orr, a 17-year Glendale fire veteran, was ultimately convicted of arson and sentenced to life without parole for the deaths.
Anyone with details about the city’s latest fires is urged to call Det. Travis Goodreau at (818) 548-3127. To remain anonymous, call Glendale Crime Stoppers at (818) 507-7867.
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