LARIMER COUNTY, Colo. If firefighters continue to make progress and weather stays favorable, crews up at the Pearl Fire north of Red Feather Lakes will begin to demobilize, officials said Thursday morning. The Pearl Fire, named after the nearby Pearl Creek, has held at 128 acres since Monday. It was first reported around 11 a.m. that day and sparked mandatory evacuations for the area around the Crystal Lakes neighborhood, which was just to the east. The Larimer County Sheriff's Office previously announced that they were in touch with a person who caused the fire and are working to verify stories about its origin. No other information was immediately available about this. One structure close to where the fire started was damaged, but no other infrastructure has been impacted, the Larimer County's Sheriff's Office said Wednesday evening. While some mandatory evacuations have been downgraded to voluntary evacuations, others still remain in place. To view the evacuation map on a bigger screen, click here. Containment increased slightly to 5% on Tuesday. That stayed the same into Thursday morning. In a video posted on Thursday morning, Incident Commander Trainee Ty Gripp provided a brief overview on the work completed Wednesday in the three divisions that make up the Pearl Fire, as shown below. Fire crews were able to construct containment lines from where Division A and Division Z meet to about halfway north along Division A, and will continue to build farther up on Thursday. In addition, crews will install hose lines to help with the mop-up process in the division. In Division K, along the northern edge of the fire, crews located two spot fires one on the northwest side and another on the northeast side and were able to construct containment lines around both of them on Wednesday. They also began constructing containment lines from east to west and got about halfway done by the end of the day. On Thursday, they will continue those efforts, Gripp said. Lastly, in Division Z along the fire's east side, firefighters mopped up some spot fires and worked along the perimeter on Wednesday, which they continued on Thursday. A group focused on structure protection in the Crystal Lakes neighborhood completed more structure assessments and finished prep around structures where it was needed on Wednesday, with a goal to keep this up into Thursday. "After today, if things are starting to look good and the weather is favorable, we will start getting rid of some of our resources, or demobilize them, because they are no longer needed on the incident," Gripp said Thursday morning. The Joint Information Center will not reopen on Friday.