(LOS ANGELES) -- A raging brush fire in Southern California spread to more than 500 acres of land in areas of Calabasas and Topanga on Sunday, putting nearly 5,000 residents in danger.
The fire was 30 percent contained as of Sunday morning after crews made "a lot of progress overnight," Los Angeles County Fire Department Deputy Chief John Tripp told ABC News.
Crews fighting the blaze included 400 firefighters and water-dropping helicopters.
Tripp said the fire is still a very large challenge on the east and south side because it's "up on a mid slope of the canyon."
"That makes it extremely dangerous ... to do a direct attack and try to get containment of that," Tripp said.
Tripp cautioned that if the sun and heat reach the fuel, the fire "could get up and start moving again like it did yesterday."
About 3,700 homes in Calabasas and Topanga were evacuated, impacting about 5,000 residents, Los Angeles Sheriff’s Department Capt. Eddie Rivero said.
Evacuations were lifted in Calabasas at 2 a.m. but mandatory evacuations for Topanga remain in place Sunday, Rivero said.
Officials cautioned that residents returning to Calabasas may be going back without power, though the specific number of power outages was not immediately clear.
Officials said a large event structure at a camp was destroyed and two single-family homes suffered damage.
Fire officials said Saturday the cause of the fire was not confirmed but there were reports that the fire had three separate starts.
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