The Mullen Fire burning in the Medicine Bow National Forest grew to 161,964 acres after an "aggressive" day on Monday.

That's according to the Mullen Fire Information Facebook page.

The post says the fire  ''grew to the north in the area of South French Creek, and in the area south of Rambler near the Rob Roy Reservoir. The fire was also very active in the area between Albany and Keystone, spotting out ahead of the main fire. Firefighters were successful in catching these spots. Late in the day crews were working in the southeast part of the fire in Division T to catch up with several spotfires that had started on the east side of Colorado Highway 127 as a result of strong winds from the northwest.''

At last report, the fire was considered to be at 14 percent containment. The blaze started on Sept. 17 in the Savage Run Wilderness area. Investigators have said they believe the fire was human-caused.