Authorities ordered Los Alamos evacuated yesterday as a fast-growing fire blazed across New Mexico, with flames coming within a mile of the famed nuclear research facility.

The 44,000-acre Las Conchas wildfire burned in the mountains above Los Alamos as firefighters spent most of their time putting out spot fires -- the biggest threat we have right now to homes in the community, Deputy Los Alamos County Fire Chief Mike Thompson said Monday.

Some 13,000 people, most of the city's residents, have been moved from Los Alamos. Those who refused to leave will be monitored by police and National Guard, officials said, NPR reported.

The hair on the back of your neck goes up, Los Alamos County fire chief Doug Tucker said of first seeing the fire in the Sante Fe National Forest on Sunday.

I saw that plume and I thought, 'Oh my God, here we go again.

Tucker said the blaze was the most active fire he has seen in his career, the Boston Globe reported; the fire also forcing the closure of the nation's preeminent nuclear lab.

All laboratory facilities will be close for all activities and non-essential employees are directed to remain off site, a statement on the laboratory's website said. Employees are considered non-essential and should not report to work unless specifically directed by their line managers.

Los Alamos is one of the leading scientific research facilities in the country and was the site of the Manhattan Project, which developed the first nuclear bomb. It continues to do research on nuclear weapons and officials emphasized that they were taking precautions to safeguard nuclear material stored at the lab.

Emergency crews have been dispatched across the lab to protect key facilities, spokesman Jeff Berger said. Protected areas include all hazardous and radioactive facilities and our proton accelerator and supercomputing centers.