Cottonwood police the reward has been raised for information about the firebombing of two private businesses and the city's Finance and Human Resources building April 1.
Evidence of Molotov cocktails were found at a Spirit Gas Station, Sun West Bank and the city building, all on Main Street, early in the morning of April 1, according to Cottonwood police spokesman Sgt. Cody Savage.
The Human Resources, Finance and Purchasing departments were temporarily moved to the Public Safety building.
Savage said damage was more than $300,000 combined.
He said Cottonwood investigators were still waiting for witnesses to come forward and that the reward had been raised to $10,000.
People with any information about the arson cases are asked to contact the Cottonwood Police Department or Yavapai Silent Witness at 1-800-932-3232.
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