Dec. 10 (UPI) — The fast-moving Franklin Fire burned more than 2,000 acres in the hills of Malibu near Pepperdine University Monday night as fire crews from the Los Angeles County Fire Department scrambled resources to contain it.

The blaze, helped along by strong Santa Ana winds, burned through 2,200 of acreage by Tuesday morning and threatened structures. Authorities said the start of the fire remained under investigation on Tuesday.

Five areas received evacuation orders and officials issued evacuation warnings to seven others. The Pacific Coast Highway in the Malibu area was closed to traffic except for those evacuating, according to the California Department of Forestry and Fire Protection.

Pepperdine University issued a statement on X telling students to remain on campus.

“The university is now activating its shelter-in-place protocol,” the university said. “All community members on the Malibu campus are directed to shelter in place in the Tyler Campus Center or Payson Library.

“Despite any evacuation orders from Malibu city or surrounding areas, the university community should follow university instructions. We do not evacuate the campus even when surrounding areas might. This shelter-in-place protocol is approved by the Los Angeles County Fire and executed with their cooperation.”

Some 12 million remain under “red flag” warnings from San Luis Obispo to San Diego because of the stiff Santa Ana winds, dry vegetation, and low humidity, heightening the conditions for additional wildfires.

Gust remains from tropical storm to hurricane strength, 50 mph to 80 mph, officials said.