Fire officials Monday continued to investigate the cause of a Saturday fire that displaced a Twain Harte family.
The fire started at the back of the house as the Gibbs family watched TV.
Some neighbors, who heard a loud bang before the fire started, wonder if it may have been started by lightning, though that could not be confirmed.
There were lightning storms in the mountains that evening.
The Gibbses are staying with a family friend.
The fire broke out in the 22000 block of South Fork Road near the Wildcat Ridge Road intersection. The fire, which burned the top of a tree and deck as well as the house, was reported to authorities at 5:42 p.m., according to Cal Fire spokeswoman Lisa Williams.
"That house was really burning," said neighbor Leroy Hutchins, who recalled counting 10 fire engines pass his house.
Damage to the structure and its contents was estimated at $500,000.
Next door neighbor and witness Walter Schipper said he heard a loud thunder-like bang before he saw fire engines arrive at the home of Mike and Linda Gibbs.
Carol Hensel, who lives with Schipper, went outside because she heard Linda Gibbs screaming.
Linda Gibbs said her house was on fire and that her husband was trying to extinguish it.
Hensel said she could see flames on the back porch of the Gibbs' house by looking through its front windows and that the blaze spread tothe inside within a few minutes.
"It was incredible," she said. "I've never seen a fire move that fast in my life."
Linda and Mike Gibbs had been watching TV in the living room at the front of their house with their son Matthew, who was visiting from the Bay Area. The couple had fallen asleep and Matthew Gibbs woke them when he noticed the fire, Hensel said.
Schipper said Matthew tried to help his father extinguish the fire, adding that a tree near the back porch was also burning.
Hensel estimated that the family had lived in the house for at least seven years and said that they had tore it down to the foundation and rebuilt it.
"They poured their hearts and souls into the house and it was pretty much near complete," Hensel said.
Local American Red Cross Director Cathie Peacock said the organization helped the family with clothing and food, but that the family chose to stay with friends.
Schipper and Hensel said the family is staying with neighbors Jim and Gay Hunt, who have an apartment above their garage.
"We have a very tight-knit neighborhood here," Hensel said. "We all care about each other and we'll help each other out."
Units from Columbia College, Pinecrest, Cedar Ridge, Tuolumne County Fire, Chinese Camp, Moccasin, Twain Harte and Tuolumne Fire responded.