A preliminary investigation into the Bisbee City Hall fire found no evidence of arson, authorities said Tuesday, Oct. 17.

The Oct. 11 fire began on the second floor in an area containing an office, which was used as storage during a renovation project, said Carol Capas, a Cochise County Sheriff's spokeswoman.

The historic building was constructed in 1909 and underwent several renovations over the last century, Capas said. She said investigators, which included structural and electrical engineers, observed older electrical wiring systems.

Capas said these wiring systems could not be ruled out as a cause for the fire due to the internal collapse of the structure.

About two dozen people were interviewed, including city hall employees and non-employees who were involved in remodeling work on the second-floor. Investigators also viewed recorded security camera footage.

"It is unfortunate that this incident claimed a valuable historical landmark, which was not only for the city of Bisbee but for all of Cochise County," said Sheriff Mark Dannels, in the news release.

The multiagency investigation was led by the Cochise County Sheriff's Office with assistance including from the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, the Gilbert Police Department K-9 unit, the Bisbee police and fire departments.

Contact reporter Carmen Duarte at cduarte@tucson.com or 573-4104. On Twitter: @cduartestar