Rescuers search for two missing people after Colorado wildfire

The flames ripped through an area of at least 9.4 square miles and left nearly 1,000 homes and other buildings destroyed in suburbs between Denver and Boulder.

It came unusually late in the year following an extremely dry autumn and a winter nearly devoid of snow. Experts say those conditions, along with high winds, helped the fire spread.

In hard-hit Louisville, Susan Hill walked her dog in the well-below freezing chill on Sunday morning down a snowy street.

She choked up as she remembered three days ago seeing the sky change colour from the hill where she used to watch fireworks — and then the nervous sprint out of town with her college-age son and the dog, cat and a fire box with birth certificates and other documents.

The flames stopped about 100 yards from her property, and she slept on Saturday night in her home using a space heater and hot water bottles to stay warm since her natural gas service had not been turned back on.

“I don’t even know how to describe it,” she said. “It’s so sad. It’s so awful. It’s just devastating.”

In the burned-out neighbourhood near Ms Hill’s home, a US Mail carrier checked the still-standing brick and stone boxes for outgoing mail.

The fire came so quickly people might have put bills or other letters in there, and she did not want someone to steal them.

While homes that burned to the foundations were still smouldering in some places, the blaze was no longer considered an immediate threat — especially with Saturday’s snow and freezing temperatures.

“A day late and a dollar short,” Ms Hill said of snow, which scientists said typically prevents winter fires that spread in dry grass.

Colorado Governor Jared Polis and federal emergency officials visited some of the damaged neighbourhoods on Sunday morning.

“I know this is a hard time in your life if you’ve lost everything or you don’t even know what you lost,” Mr Polis said after the tour. “A few days ago you were celebrating Christmas at home and hanging your stockings and now home and hearth have been destroyed.”

The cause of the fire is still under investigation. Utility officials found no downed power lines around where the fire broke out.

Boulder County Sheriff Joe Pelle said on Saturday that authorities were pursuing a number of tips and had executed a search warrant at “one particular location”.

Authorities initially said everyone was accounted for after the fire. But Boulder County spokesperson Jennifer Churchill said the reports of three people missing were later discovered amid the scramble to manage the emergency. One has since been found safe.

The search for the other two missing people was complicated by still burning debris and the snow,.

Of at least 991 buildings destroyed by the fire, most were homes. But the blaze also burned through eight businesses at a shopping centre in Louisville, including a nail salon and a Subway restaurant.

In neighbouring Superior, 12 businesses were damaged, including a Target, Chuck E Cheese, Tesla dealership, a hotel and the town hall.

The two towns are about 20 miles north west of Denver with a combined population of 34,000.