BOULDER COUNTY, Colo. — The cause of the state’s most destructive wildfire is yet to be determined but the area where it is believed to have started has been narrowed down, according to the Boulder County Sheriff’s Office.
When wind speeds started to howl — reaching upwards of 100 mph Thursday — Mike Zoltowski saw a fire truck near his home by the intersection of Colorado 93 and Marshall Road in unincorporated Boulder County
“This is going to be... this is going to be ugly,” he said.
Stepping outside his house, he saw a shed on fire just yards away from his front door.
"For about 45 minutes, this went on. Then, all of a sudden, another fire started at this corner,” he said. “That's when I got a little bit nervous about my situation."
Zoltowski’s home wasn't in the path of the blaze, though winds whipped loose fence posts against his home.
READ MORE: How to help the people affected by the Marshall Fire in Boulder County
Boulder County Sheriff Joe Pelle said investigators believe the fire started in the neighborhood off Colorado 93 and Marshall Road.
The blaze, fueled by hurricane-force winds, burned over 6,000 acres and destroyed about 1,000 homes and businesses in Superior, Louisville and unincorporated Boulder County.
"It's really obvious where that fire started and what direction it went in,” Pelle said.
The foot of snow that followed the fire isn't helping in the search to determine the cause.
“We will sort it out. It’s an active, open deal and the outcome of that investigation is vital. There is so much at stake. So we are going to be careful,” Pelle said.
Pelle said investigators have spoken to witnesses, but he didn't say if those involved are cooperating with police.
On Sunday, the area around the shed was fenced off and under investigation.
Top state officials said they will hold someone accountable if the blaze was set intentionally or recklessly.
“Something ignited the fire, in the wind, on a red flag day. Our job and responsibility and our quest are to determine what started that fire,” Pelle said.
The FBI and the ATF are assisting as part of the investigation.
Downed power lines have not been ruled out, but Xcel Energy crews did not find any power lines in the area, according to Boulder County officials on Friday. They did find compromised communication lines, but those would not typically cause a fire.