JEFFERSON COUNTY, Colorado — Deer Creek Canyon Park reopens Thursday after a wildfire Aug. 15 closed the area. Rattlesnake Gulch Trail will remain closed for erosion control, Jeffco Open Space said in a tweet.

Firefighters now believe the fire near the park that led to hundreds of evacuations was human-caused.

"We've talked with witnesses," Jefferson County Sheriff's Office spokesperson Mike Taplin said. "The witnesses have heard explosions. They saw smoke and then some witnesses have seen two juvenile males running from the area." 

More than 100 firefighters worked throughout the night — until about 2 a.m — to knock out flames from the 13.5-acre fire, Jefferson County Sheriff's Office Taplin said during a media briefing Friday morning. 

The Jeffco Sheriff's Office tweeted Friday afternoon that the fire is now 100% contained and previous evacuation orders have been lifted.

So far, no injuries have been reported and no structures have been lost, Taplin said. Firefighters worked Friday to improve the perimeter of the fire line and attack hot spots within the burn area.  

CodeRed evacuation notices were sent to 314 homes in the area on Thursday. Homes in the White Deer Valley and Deer Creek Mesa neighborhoods were affected, as well as the area near Samson Road, Mill Hollow Road and Sunburst and Hunter's Ridge neighborhoods. 

Evac map
Evacuation zone map
Jeffco Sheriff

The investigation into the fire remains open.  Anyone with information that may be helpful to the investigation is asked to call 303-271-0211. 

Taplin described the blaze as a “dirty burn” — meaning there was significant amounts of unburned fuel within the fire perimeter that required extensive work to dig into smoldering vegetation. 

Inter-Canyon said steep terrain and heavy oak fuels were challenging for crews. Taplin asked that residents in the area refrain from using drones, as it can hinder firefighting efforts.

Brian Ferguson has lived in the area for 17 years and said the fire was "close enough to be concerned." If the fire was human caused, Ferguson said he hopes it teaches a lesson. 

"I don't want those kids' life to be ruined, but I want them somehow to be scared straight out of doing something like that again," he said. 

WATCH BELOW | Raw SKY9 video of the fire

RELATED: Firefighting helicopters in Colorado are now allowed to fly at night

The fire was reported around 4:45 p.m. after neighbors noticed smoke and flames. South Valley Park will reopen Saturday morning. Deer Creek Canyon Park and Hildebrand Ranch Park will remain closed until further notice.

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