A brand-new quickly spreading wildfire starts up north of Los Angeles.

31,000 people were forced to evacuate after a swiftly spreading wildfire broke out north of Los Angeles.

While two large flames that had been raging in the metropolitan area for more than two weeks were being brought under control, a swiftly spreading wildfire erupted north of Los Angeles, according to fire officials.

On Wednesday, fierce fires ravaged the mountains close to Castaic Lake, quickly engulfing nearly 9,400 acres (3,800 hectares) in a matter of hours.

31,000 people were ordered to evacuate the area around the lake, which is located near the city of Santa Clarita and 56 kilometres (35 miles) north of Los Angeles.

The whole 700,000-acre (2,800 square km) San Gabriel Mountains park is closed to visitors, according to the US Forest Service.

The two fatal flames that have devastated Los Angeles were brought under better control as the new fire burned, according to the California Department of Forestry and Fire Protection (Cal Fire).

According to Cal Fire, since the two fires started on January 7, they have destroyed or damaged around 16,000 buildings, scorched an area almost the size of Washington, DC, and claimed 28 lives.

AccuWeather, a private forecaster, estimates that economic losses and destruction would exceed $250 billion.

The Hughes fire at Castaic Lake is fought by firefighters.Firefighters watch the flames from the Hughes fire scorch the hillside in Castaic, a community in northwest Los Angeles County.