CONIFER, Colo. (AP) -- Colorado Gov. John Hickenlooper on Wednesday suspended the use of state prescribed burns like the one that may have caused a deadly wildfire that destroyed dozens of homes near Denver.
Investigators were trying to determine whether the 6-square-mile fire reignited from a controlled burn that was meant to reduce vegetation that could fuel a devastating blaze around homes and watersheds.
Hickenlooper said the ban on such fires on state lands, including state parks, would be in effect until a review of the wildfire is complete.
The ban doesn't affect land controlled by the federal government -- which accounts for over a third of Colorado. However, Hickenlooper urged counties and federal agencies to also consider suspending such burns for now.
Meanwhile, some 400 firefighters from several states were focusing on building containment lines around the wildfire, which broke out Monday. Until now, the fire's erratic pattern has forced firefighters to focus on protecting homes, not stopping the burn.
"We're going to try to take a bite out of this fire," Jefferson County sheriff's spokeswoman Jacki Kelley said.
Air tankers dropped retardant and two National Guard helicopters dropped water to assist firefighters on the ground. Smoke from the fire created haze around Denver, obscuring views of the Rocky Mountains.
As crews dug lines around the fire's perimeter, a search team was using dogs to look for a woman missing in the fire zone. Her home was among 27 destroyed or damaged in the blaze.
The bodies of Sam Lamar Lucas, 77, and Linda M. Lucas, 76, were found earlier this week at their destroyed home. Their cause of death was pending.
Investigators were looking into a 35-acre burn that the Colorado State Forest Service conducted in the region Thursday on land belonging to Denver's water authority. Crews finished the effort Friday and patrolled the perimeter daily to ensure it was out, said forest service spokesman Ryan Lockwood. It was during Monday's patrol that a state forest service crew spotted the wildfire -- also on Denver Water property -- and alerted authorities, Lockwood said.
It wasn't clear if the wildfire, dubbed the Lower North Fork fire, was inside the controlled burn zone.
Hickenlooper said he doesn't blame some of the 900 evacuated homeowners in the mountains southwest of Denver for being angry.
"Their houses have been destroyed. Their lives have been changed forever. It's not their fault," Hickenlooper told KOA radio.
A Forest Service manager who helps plan for prescribed burns, Jane Lopez, said the state usually performs them only in spring and fall. Prescribed burns are planned as far as three years in advance, she said, but they don't go forward unless weather conditions meet requirements. She said everything was done properly.
"You don't burn unless all the parameters are met," Lopez said. She didn't comment on the governor's planned burn order but said, "We're at the end of the prescribed burn season anyway."
The Jefferson County sheriff's office and Colorado Bureau of Investigation will determine the cause of the blaze. The Colorado State Forest Service was conducting its own review.
Conifer resident Don Heiden, who was displaced by the fire, said he wasn't ready to blame the government.
"Accidents happen. If there was negligence, they'll figure it out," said Heiden, who was watching televised aerial shots to see if his home was still standing. "To me, it's more of an act of God."
For years, fire agencies have used controlled burns to pre-empt devastating wildfires by consuming fuel. Officials credited such an operation with helping save hundreds of homes during a 2002 Colorado wildfire that did destroy 133 homes.
A few controlled burns have escaped firefighters' control.
One of the worst cases was in New Mexico in 2000. A prescribed burn set by the National Park Service in Bandelier National Monument, west of Los Alamos, blew out of control, and all of Los Alamos was evacuated. More than 400 families lost their homes and more than 115 Los Alamos National Laboratory buildings were destroyed or damaged. The federal government paid $455 million in compensation.
The Park Service resumed prescribed burns a year later with new rules, including having outside experts check burn plans.
The fire threat in much of Colorado has grown during an unusually dry and warm March. Several counties, including Jefferson, have implemented fire restrictions affecting campfires, fireworks and smoking in fire-prone areas.
Associated Press writers Rema Rahman, Steven K. Paulson and Kristen Wyatt in Denver contributed to this report.