Smoke rises from the Hermits Peak and Calf Canyon wildfires.
CNN  — 

Two wildfires that combined in New Mexico have prompted the evacuation of thousands of people – and much of the state is expected to be under a critical fire threat Tuesday.

The Calf Canyon fire started on April 19 and joined with the Hermits Peak fire, which started April 6.

The combined blaze had burned more than 145,000 acres by early Tuesday and is just 20% contained, according to Inciweb. More than 1,000 fire personnel have been called in to battle the flames, according to Inciweb’s incident report.

The fire’s rapid spread prompted evacuation orders Friday in an near San Miguel County, officials said. About 3,500 people had been evacuated in and around the city of Las Vegas as of Monday evening because of the fire threat, according to San Miguel County Manager Joy Ansley. As of Friday, 270 structures had been visibly damaged or destroyed, including 166 homes, she said. Las Vegas is located about 70 miles east of Santa Fe, New Mexico.

Parts of the state were already under critical fire threat Monday and that threat was expected to expand Tuesday to cover nearly all of New Mexico, said CNN meteorologist Robert Shackelford.

A satellite image showing the Hermit Peak fire east of Santa Fe, New Mexico, on Sunday, May 1.

On Monday morning, the Behavioral Health Institute in Las Vegas began evacuating all 197 of its patients, including adult psychiatric patients and children, the New Mexico Department of Health announced. The acting health secretary Dr. David R. Scrase thanked the facility’s staff for their commitment to relocating the patients safely.

“Many of our caregivers live in the area that burned and many still don’t know if their homes are still standing – still, they put their patients first,” he said.

More fires continue to burn in other areas the state, including the recently ignited Bear Trap fire in the southwest, which InciWeb says was first reported Sunday.

Other parts of the Southwest, including Arizona and Colorado, are also experiencing wildfire destruction. Small portions of northeast Arizona and southern Colorado are also expected to fall under critical fire threat Tuesday, according to Shackelford.

CNN’s Paul Murphy and Joe Sutton contributed to this report.