A raging wildfire fanned by strong Santa Ana winds has spread to nearly 4,000 acres in Malibu, California, destroying homes and leaving more than 20,000 people under evacuation orders, including 98-year-old actor Dick Van Dyke and other celebrities in the oceanfront community.

The Franklin Fire, which erupted Monday night near the campus of Pepperdine University, was 7% contained on Wednesday morning as more than 1,500 firefighters were deployed to battle the blaze in the rugged and hilly terrain of Malibu Canyon, according to the California Department of Forestry and Fire Protection (Cal Fire).

Burning through thick dry vegetation, the fire has been fueled by Santa Ana winds that have topped 90 mph, officials said.

In a message posted on his Facebook page, Van Dyke, who is set to turn 99 on Friday, said he and his wife, Arlene, were forced to evacuate as flames threatened their home in the secluded community of Serra Retreat in the hills of lower Malibu Canyon. He said all of his pets, except for his beloved cat Bobo, managed to escape.

"Arlene and I have safely evacuated with our animals except for Bobo...," Van Dyke wrote. "We're praying he'll be ok and that our community in Serra Retreat will survive these terrible fires."

In a follow-up Facebook message, Van Dyke posted a video of his cat, writing, "Hoping Bobo is ok."

Other celebrities residing in the area were forced to flee the flames or stay on lockdown. Recent Rock and Roll Hall of Fame inductee Cher also evacuated, according to her publicist.

"Star Wars" actor Mark Hamill said in an Instagram post that he has also been affected by the fire.

"We're in lockdown because of the Malibu fires," the 73-year-old Hamill said in the post. "Please stay safe everyone! I'm not allowed to leave the house, which fits in perfectly with my elderly-recluse lifestyle."

The Franklin Fire erupted just before 11 p.m. Pacific time on Monday and quickly grew amid the blustery Santa Anna winds, which blow southwest toward the Pacific Ocean.

At least seven homes have been destroyed by the fire and another eight have been damaged, according to Cal Fire.

Power to about 40,000 customers was shut off by Monday night, including 11,000 in Los Angeles County, as Southern California Edison worked to mitigate the impacts of the Santa Ana winds, whose strong gusts can damage electrical equipment and spark more wildfires.

There have been no reports of deaths or injuries. The cause of the fire remains under investigation.

Pepperdine University canceled classes for the second straight day. When the fire erupted, officials put the campus on lockdown for about six hours before the order was lifted. As the fire grew on Tuesday, students were again ordered to seek shelter in the campus center and library, where students said they watched flames creep onto campus.

"Fire activity around Pepperdine's Malibu campus has greatly diminished as the Franklin Fire has burned through most of the fuel immediately surrounding campus, but some flames are still visible in small pockets of campus," the university said on its website.

Malibu resident Fred Robert described to ABC News seeing flames "coming straight down Malibu Canyon like a blowtorch."

Red Flag warnings issued by the National Weather Service signaling the high risk of fire danger remained in effect Wednesday in the Malibu area.

"Time is of the essence for us to grab hold of the fire and start getting containment," Los Angeles County Fire Chief Anthony C. Marrone said at a news conference Tuesday evening.

Marrone said firefighters are tackling the blaze from the ground and air "as they struggle to contain this stubborn fire."