State highway officials closed off Highway 15 Monday to bar motorist access to the historic site; however, monument Superintendent Steve Riley said there had been a number of intruders after hours.
"We were having all kinds of after-hours intrusions," Riley told the Silver City (N.M.) Sun-News.
In recent days, someone removed rocks from one of the dwellings' walls.
"Those walls are original, and my first responsibility is to preserve and protect for future generations," Riley said.
The Whitewater-Baldy fire, said to be the largest wildfire in New Mexico's recorded history, was last reported by KOB.com Monday to be 18 percent contained, having already burned through 255,024 acres.
Riley told the Sun-News much of his staff had been evacuated due to the heavy smoke, but he planned to hold back one or two people.
"It's the worst I've seen it in the 10 years I've been here," he said. "We have visibility of less than a quarter mile some mornings."