BOULDER, Colo. — Investigators seeking the cause of the Colorado wildfire that destroyed nearly 1,000 buildings have narrowed their search to an area near Boulder, but it could be days or weeks before details are released, the sheriff said Monday.

The search is focused on an area where a passer-by captured video of a burning shed on the day the fire began, Boulder County Sheriff Joe Pelle said at a news briefing. He said dozens of people have been interviewed thus far.

Experts from the FBI, the Bureau of Alcohol, Tobacco, Firearms and Explosives, and the U.S. Forest Service were participating in the investigation, Pelle said.

The sheriff declined to offer many more details on Monday, a day after saying that the fire “originated somewhere” in the neighborhood with the burning shed.

Declaring that “the stakes are huge,” Pelle said he would not comment on the probe until he was ready “to announce some progress — perhaps that may be a week, perhaps that may be a month.”

Getting it right, he said, was “more important than the urge for speed that a lot of folks are feeling right now.”

Experts say the winter fire was rare but that similar events will become more common as climate change warms the planet and suburbs grow in fire-prone areas. The inferno broke out unusually late in the year following months of drought that included a dry fall and a winter with hardly any snow so far.