A wildfire ramped out of control Monday in woodland outside of Los Angeles while meteorologists warned about the threat of fire conditions in the parched west after a weekend of record temperatures.

The pipeline fire, reported only six miles north of Flagstaff on Sunday morning, has increased to about 6.000 hectares, according to the National Interagency Fire Center.

South-west was afflicted by a one-off drought which made the vegetation extremely dry and flammable.

More than three million people in Arizona, Colorado, New Mexico, and Utah, were subject to red flag warnings Monday which highlighted the heightened fire risk.

In New Mexico, hundreds of thousands of acres of forest have been devastated in forest fires that have burned for months.

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