A father and son who were in the vicinity of the ignition point of the massive Caldor Fire in August, and who made the first 911 calls about the wildfire, are now under arrest and set to be charged with wildfire arson.

David Scott Smith, 66, and Travis Shane Smith, 32, are being charged with "reckless arson," after investigators have come to believe that the pair were responsible for igniting the fire that ultimately grew to 221,835 acres in El Dorado, Amador and Alpine counties, flattening the town of Grizzly Flat, and forced the dramatic evacuation of South Lake Tahoe.

The Caldor Fire grew rapidly in its first days after starting on August 14, exploding from 6,500 acres on August 17 to over 30,000 acres by that evening, and 53,000 acres by the next day.

As the Sacramento Bee reports, the Smiths had been spotted in a dune buggy in the area just as the fire began east of Omo Ranch, south of Grizzly Flat. Travis Smith, of Folsom, is an electrician, and an attorney for the pair, Mark Reichel, says that he and his father were just the first to spot the flames and report them.

"There is no reason at all to try to imagine what could have happened out there until actual evidence and theories from the prosecution are presented in a courtroom,” Reichel said to the Bee. “There is no reason that this person would set a fire unless it was an accident and not intended."

Reichel added that the younger Smith repeatedly called 911 because the call kept dropping in this remote area.

Investigators with El Dorado County District Attorney Vern Pierson’s office have reportedly been looking into the case for several months.

As the Bee reports, the men were arrested Wednesday on what's called a “Ramey warrant,” because formal charges have not yet been filed.

We are incredibly grateful for the work put into this investigation by all agencies involved, and look forward to following the process of prosecuting these arsonists,” said the South Lake Tahoe Police Department in a statement on Facebook.

In a statement on Facebook, the South Lake Tahoe Police Department said, "We are incredibly grateful for the work put into this investigation by all agencies involved, and look forward to following the process of prosecuting these arsonists."

Related: South Lake Tahoe Spared Another Night From Caldor Fire

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