Firefighters are braced for an “unprecedented extreme wind event” and near-record high temperatures to fan the largest blaze burning in the US, which has already caused widespread devastation and prompted thousands to flee.

Forecasters in the US are warning gusts could reach up to 60mph over the weekend, fuelling the spread of the wildfire in northeastern New Mexico that has scorched more than 262 square miles in recent weeks.

At least 165 homes have gone up in flames since the fire erupted, while thousands more have been evacuated.

It is hoped action taken to tackle the blaze including clearing vegetation and digging firebreaks will prevent it reaching the city of Las Vegas, which is distinct from its larger and better-known namesake in Nevada.

Elmo Baca, chairman of the Las Vegas Community Foundation, said: “There’s uncertainty and there’s fear about how the winds are going to affect the fire from day to day.

“Once the people are evacuated out of an area, they can’t go back, so they’re just stuck worrying.”

The start of the fire has been traced in part to preventive work undertaken by the US Forest Service in early April to reduce flammable brush.

Spreading out of control, it merged with another wildfire, the cause of which is unknown.

Long-term drought and warmer temperatures caused by climate change have combined to worsen the threat of wildfire.

Forests in southern New Mexico, Arizona and Colorado have also seen destructive blazes.

Incident commander Dave Bales said firefighters dealing with the current blaze in northeastern New Mexico had dealt with high winds before, but he pointed out the current weather could last five days or more days.

He also warned flames could be carried up to a mile away.

“This is an extreme wind event that is unprecedented,” Mr Bales said.

Another large wildfire burning in New Mexico was within five miles of Los Alamos National Laboratory, the country’s leading nuclear weapons research facility.

Crews have burned vegetation ahead of the fire in a bid to reduce its intensity.

At the lab, water tankers, a helicopter and heavy equipment are in position and firefighters will patrol the perimeter if flames get any closer.

Some nuclear watchdog groups and environmentalists have raised concerns about containers of nuclear waste at the site.

Lab officials said radiological and other potentially hazardous materials are stored in containers engineered and tested to withstand extreme environments, including heat from fire.