RENO, Nev. — One of the men charged with starting the devastating Caldor Fire in California is charged with converting a firearm into a machine gun, according to a criminal complaint filed by the El Dorado County District Attorney’s Office.

Both David Smith, 66, of Somerset and his son Travis Smith, 32, of Folsom, California, are facing multiple felony counts, which includes both facing a charge of possessing a silencer between Aug. 11 and Sept. 23.

Only Travis Smith is charged with machine gun conversion — converting a firearm into a machine gun or manufacturing a machine gun — between Aug. 9 and Aug. 14.

In addition, both are facing three felony counts of recklessly starting a fire that damaged property, land and people. One of the charges includes four enhancements, which could increase the possible sentence.

The enhancements include injuring a firefighter or peace offer as a result of the fire; causing bodily harm to more than one victim; causing multiple structures to burn; and doing so during a state of emergency.

The men pleaded not guilty to several felony charges in an El Dorado County courtroom on Friday.

David Smith's attorney, Linda Parisi, said after the hearing that she has no idea what prosecutors think started the fire. Parisi told Judge Mark Ralphs that neither she nor attorney Mark Reichel, representing Travis Smith, have been presented with any evidence showing their clients' guilt.

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California Gov. Gavin Newsom had declared a state of emergency for El Dorado County in May. The Caldor Fire burned more than 200,000 acres along the Highway 50 corridor between Pollock Pines and South Lake Tahoe.

Two civilians in the Grizzly Flats area were severely injured and one firefighter also sustained injuries in the fire. It forced abouyt 50,000 people to evacuate along the Highway 50 corridor and in the Lake Tahoe Basin, including the entire city of South Lake Tahoe.

Nearly 32,000 structures were threatened, 81 were damaged and almost 800 were destroyed. The fire also leveled the town of Grizzly Flats, located about 12 miles east of Somerset, and destroyed hundreds of acres of ski runs at Sierra-at-Tahoe, one of the closest resorts to the Bay Area and Sacramento.

The Smiths' attorney, Sacramento-based criminal defense attorney Mark Reichel, told the USA TODAY Network that Travis Smith called 911 after spotting the flames, and were in the area where the fire originated. Reichel said he is unaware of what evidence investigators believe links his clients to the start of the fire, but maintained they "definitely were not intentionally setting a fire."

"They are 100% innocent of the charges," said Reichel.

Contributing: Jeanine Santucci, USA TODAY

This article originally appeared on Reno Gazette Journal: Caldor Fire suspects: Man charged with manufacturing a maching gun