The causes of three suspicious fires that prompted evacuations and destroyed property in the Jamestown area in late July and early August are still officially undetermined, though they all occurred more than six weeks ago.

Cal Fire Tuolumne-Calaveras Unit staff are investigating causes of the Jacksonville Fire and the Twist Fire. Tuolumne County Fire Prevention staff are investigating the cause of the Golf Fire.

The Jacksonville and Twist fires were separate and distinct, with different points of origin, Matthew Gilbert, a Cal Fire battalion chief in charge of Fire Prevention and Law Enforcement, confirmed.

“No updates as of now,” Gilbert said. “Nothing new to report on those two.”

Asked for more details on what is known and what is not known about how the Jacksonville and Twist fires started, Gilbert confirmed again the points of origin were near Jacksonville and Twist roads, respectively.

“We don’t want to release any information that could jeopardize the investigations,” Gilbert said. “We’re still trying to figure out what happened out there. We don’t want to put out what we believe or what's an opinion. We want to make sure we know what happened.”

Gilbert underscored that no one with Cal Fire has publicly stated whether the causes of the Jacksonville Fire or the Twist Fire have been determined to be arson or accidental.

Asked why it’s so complicated, if investigators already know the causes and aren’t saying, and if the trail toward possible suspects has gone cold, Gilbert said, “In an ideal world there is information that is likely known only to someone who may have started a fire, and we wouldn’t want to compromise that by releasing details.”

The Jacksonville Fire and Twist Fire broke out within less than a mile of each other on consecutive days in late July and burned more than 800 acres southeast of Jamestown.

The fast-moving Jacksonville Fire prompted rolling evacuations and aggressive aerial attacks as it burned northeast from Jacksonville Road across cured-dry grass ranchlands toward Algerine Road and Twist Road on July 29.

The Twist Fire broke out the next day next to Twist Road and burned quickly from grasslands to heavier fuels on Hog Mountain, prompting more aerial attacks, raising concerns among cattlemen, and destroying a ranch home and property.

Cal Fire Tuolumne-Calaveras Unit staff have not offered a reward for information about how the Jacksonville and Twist fires started, Gilbert said.

The Golf Fire broke out the evening of Aug. 9 near a new subdivision called Boulders at 10655 Golf Links Road, where it destroyed one new home and damaged two others. Damage from the blaze was estimated to be about $250,000, said Steve Gregory with Tuolumne County Fire Prevention, who is investigating the cause of the Golf Fire.

The cause of the Golf Fire remains undetermined, Gregory said earlier this week.

Anyone with information about how the Jacksonville Fire and Twist Fire started can call Tuolumne-Calaveras Unit headquarters in San Andreas at (209) 754-3831, Gilbert said. Anyone with information on how the Golf Fire started can call Tuolumne County Fire Prevention at (209) 533-5633.

Contact Guy McCarthy at or (209) 588-4585. Follow him on Twitter @GuyMcCarthy.