Investigators with the Butte County Sheriff's Office located the five fatalities in the area of Edgewood Lane in the town of Paradise in Butte County, about 130 km north of California State's capital Sacramento.
"The preliminary investigation revealed that the victims were located in vehicles that were overcome by the Camp Fire," said the sheriff's office in a release, adding that identification could not be immediately made due to burn injuries.
The Butte County Coroner's Office has formed an interagency team to investigate and identify additional fatalities, according to the release.
Only a day after it erupted, the wildfire near the town of Paradise had grown to nearly 110 square miles (285 square km).
The sheriff's office has received reports of fatalities due to the fire, and investigators are still working to confirm the reports, Sheriff Kory Honea said in the release. "The task is difficult as the fire is still active and there are many hazards in areas where fatalities have been reported."
The sheriff encouraged residents to check safeandwell.org to locate their loved ones, or contact the office at 5305387322 to request a welfare check or file a missing person's report.
The rapidly expanding Camp fire blazing through Northern California has disrupted phone and internet service, according to Butte County.
"The County website and network are down due to the campfire. This means some phone numbers are down. All numbers starting with the prefix 552-XXXX are down. Numbers starting with 538-XXXX should be working," the county tweeted on Friday morning.
The initial five reported deaths put the Camp Fire among the 20 deadliest fires in California modern history, according to Cal Fire. The worst was the Griffith Fire in Los Angeles in 1933, when 29 died.
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