One firefighter suffered a minor injury to his eye, the Los Angeles Fire Department (LAFD) said. No homes or other structures have burned.
Some drizzly rain in the area and an inversion layer have helped prevent the fire from spreading. That marine layer tends to trap heat, and Garcetti warned that once the clouds lift, typically in the afternoon, flames have the potential to take off rapidly.
The arson suspect, an adult man, is currently receiving medical treatment for smoke inhalation.
The LAFD had previously said there was a “suspicious start” to the fire, and on Saturday briefly detained and then released a different person. Fire Chief Ralph Terrazas expressed confidence Monday they had the correct suspect now in custody.
“It is an active investigation,” he said. “I can’t give you more details than that, but the person in custody — we feel we have the right person.”
About 1,000 people evacuated
More than 500 firefighters are combating the flames in a challenging canyon terrain that’s filled with 20-30 foot brush that hasn’t burned in about 75 years, Garcetti said.
“Gather your valuables, medicines etc and load them into your car so you are ready if asked to evacuate,” the department said.
Roughly 300 firefighters battled the blaze over the weekend, Ortiz said.
“There’s a lot of dense, thick material there, oily plants that have dried out because of the drought,” Ortiz said Sunday. “So, that’s our objective today: to try to keep it out of that and protect the communities and neighborhoods that are to the west of this fire because that’s what’s closest to it.”
Those drought conditions, coupled with the gusty winds the area is expected to see in the coming days, will likely pose some of the biggest challenges in containing the fire.
CNN’s Paul Vercammen, Hollie Silverman, Andy Rose and Alaa Elassar and Jenn Selva contributed to this report.