Authorities are trying to locate the two missing people from the huge Colorado fire while those who survived the blaze dealt with the debris of their homes, hoping to retrieve their belongings, ABC News reported.

The fire, which raged through at least 24 square kilometer-area, left about a thousand houses and other infrastructures wrecked in suburbs between Boulder and Denver.

The cause of the fire that started Thursday is still being determined by investigators.

The blaze started after an intensely dry fall and in the middle of winter. The spread of the inferno was fueled by the said conditions, in addition to high winds.

Authorities are following several tips and issued a search warrant at “one particular location,” said Boulder County Sheriff Joe Pelle.

No additional details were released by the sheriff on Sunday. He also did not specify whether arson is included in the possible cause of the fire.

“It’s complicated and it’s all covered with a foot of snow,” the sheriff said. “The outcome of that investigation is vital — there is so much at stake. We are going to be professional. We are going to be careful.”

Among the affected residents were Rex and Barba Hickman who went through their gutted house in Louisville.

Austin, the couple’s son, used a grinding tool to open a safe and retrieve the couple’s passport, along with keys, silver coins, and melted credit cards from there.

They managed to get out of their house with their pet dog, some clothes and their iPads. The sight of their home for 23 years, burning, hurts Rex Hickman.

“There’s a numbness that hits you first. You know, kind of like you go into crisis mode. You think about what you can do, what you can’t do,” he said. “The real pain is going to sink in over time.”

In the meantime, the family has to find a rental home and clothes. They were informed by their insurance company on Sunday that their home will be rebuilt for at least a couple of years.

“We know how fortunate we are,” Rex Hickman said. “We have each other. We have great friends, wonderful family. So many people have got to be suffering much more than we are, and we feel for them.”

Two persons – involving a man residing near Marshall and a woman in Superior – went missing.

Their houses were “deep in hot debris and covered with snow. It is a difficult task,” Pelle said.

Pelle added that investigators are looking at the possibility that the missing persons have survived the fire but have not yet communicated with their families.