Franklin Fire rages across Puerco Canyon in Malibu.

Footage shows intense flames sweeping across hillsides as firefighting helicopters fly overhead, attempting to contain the spreading blaze on December 10.

The Ventura County Fire Department (VCFD) Air Unit, utilising Firehawk helicopters with night vision capabilities, supported Los Angeles County Fire in critical night operations.

Ground crews, including strike teams, dozers, and hand crews, worked to reinforce containment lines with retardant drops and handline construction.

Authorities said the Franklin Fire started at 10:52 pm on December 9, quickly spreading to 300 acres.

Mandatory evacuations were issued for areas east of Malibu Canyon Road, south of Piuma Road, and the Serra Retreat area.

Parts of Pacific Coast Highway and Topanga Canyon Boulevard were closed due to the fire.

The blaze erupted during strong Santa Ana winds, which occur when air from high pressure over the Great Basin flows westward toward lower pressure off the California coast. This air accelerates, sinks, and compresses as it moves through mountain passes, reaching up to 70 miles per hour.

By Wednesday, the fire had burned around 4,035 acres. The cause is still unknown.