DENVER - While firefighters have contained both wildfires that burned 21,000 acres in Colorado last week, destroying dozens of homes, hot spots still exist and fire danger remains high in southern and western Colorado.
At their height, the Hi Meadow and Bobcat fires drew some 1,600 firefighters to the Front Range foothills since they began June 12, but only about 200 remained on the job Wednesday, said Dave Steinke, a U.S. Forest Service spokesman in Denver.
He said authorities are setting up three tactical groups with about 70 members in an effort to quickly put down any new fires before they grow large.
The groups, mostly manned by fresh crews that did not fight the Colorado fires or had several days left in their 14-day shifts, were being stationed in the Durango, Pueblo and Grand Junction areas, Steinke said.
Also Wednesday, authorities said people, not lightning or other natural phenomena, started the fires.
Officials investigating the Hi Meadow fire 35 miles southwest of Denver, which destroyed 51 homes, have ruled out lightning as the cause and are asking anyone with information to come forward, Forest Service spokesman Lynn Young said.
''We know the origin of the fire, we know the cause of the fire,'' said Park County Sheriff Fred Wegener. ''We're just not releasing the cause (because) it's the only control we have in the investigation.''
He said investigators do not have any suspects.
A man suspected of starting the Bobcat fire, which burned 22 structures near Rocky Mountain National Park northwest of Denver, has refused to talk to sheriff's deputies in Larimer County.
Officials have said they believe Kenneth Winchester, 33, of Loveland, lit a campfire that caused the blaze. They are still investigating the case without his help, sheriff's spokeswoman Cindy Gordon said.
Larimer County authorities said prosecutors could seek a felony charge for every house destroyed by the fires.
Firefighters are using thermal imaging technology to pinpoint hot spots. Crews then are sent out with either global positioning system devices or maps to find those spots, said Gina Owens, spokeswoman at the Hi Meadow fire.
Rehabilitation efforts continued with crews installing water bars to prevent erosion, she said.
Officials do not yet know when either fire will be declared controlled, but Steinke said there is little danger either fire could escape containment lines.
