As hundreds of thousands of Los Angeles commuters scrambled on Monday to navigate the shutdown of one of the busiest stretches of freeway in Southern California, the state authorities said they now believed that arson had caused the huge fire that exploded early Saturday from a storage yard and forced the indefinite closure of Interstate 10.
Gov. Gavin Newsom of California said in a news conference on Monday afternoon that it was too soon to know who set the blaze, which erupted within a fenced area of concrete infrastructure abutting a downtown Los Angeles industrial district.
However, he said, investigators scouring the site have made a preliminary determination that the blaze was intentionally started within an enclosure filled with wooden pallets, as opposed to originating in one of the encampments of homeless people nearby.
“Arson appears to be the likely ignition for this fire,” Mr. Newsom said. “There was malice intent.”
The distinction is politically significant as the public has become increasingly frustrated over homeless camps in Los Angeles and other California cities, seeing them as a blight on neighborhoods and a threat to public safety. Some critics were quick this weekend to suggest that homeless campers might have been responsible for the latest blaze, which shuttered a freeway traversed by about 300,000 vehicles daily.
Kevin de León, the Los Angeles city councilman whose downtown district includes the industrial stretch where the weekend fire started, said that he had received a number of complaints from business owners who were concerned about fire and other hazards and that homeless outreach staff members from his office had gone out several times since July to visit at least two homeless encampments under Interstate 10, seeking to move residents into shelter.
“It’s an ongoing issue, but I don’t want to conflate it with the source of this fire,” Mr. de León said. “We need to see where the investigation goes.”
Mayor Karen Bass of Los Angeles similarly urged caution and asked the public to refrain from jumping to conclusions about who had set the fire. She said that after the fire, 16 homeless people had been moved from local encampments into temporary housing, including a pregnant woman. No injuries were reported in the blaze, which was extinguished in several hours on Saturday.
“We need to make sure that as Angelenos, we never ever turn on each other,” she said. “We know that the origin of this is arson. We do not know other information. There is no reason to assume that the origin of this fire or the reason this fire happened was because there were unhoused individuals nearby.”
The governor’s update came as structural engineers tested core samples of rebar and concrete from the blackened columns that hold up the freeway, seeking to determine whether the structure could be repaired and eventually reopened, or whether it would have to be demolished and completely rebuilt.
The authorities said that either way, it was unclear how long repairs might take, and warned Los Angeles residents that detours around Interstate 10 would be necessary for the foreseeable future. “The structural integrity of the deck appears to be much stronger than was originally assessed,” Mr. Newsom said, but he added that more than 100 columns had been damaged, “nine or 10 quite severely.”
On Monday, on commutes that already are typically only a fender-bender away from gridlock, Southern California drivers endured bumper-to-bumper traffic on I-10 detours and braced for yet another stressful variable — rain coming later in the week. Mayor Bass urged Southern California residents to stay home and work remotely if possible, and she suggested that they use the city’s Metro transit system if they had to travel.
The governor said the property where the fire was initially reported, in the 1700 block of East 14th Street, is owned by the California Department of Transportation. But the so-called airspace under the freeway offramps had been leased to Apex Development Inc., a Southern California construction company to whom he referred as “a bad actor.”
Calls to Apex requesting comment on Monday were not returned.
According to documents filed in Los Angeles Superior Court, a five-year lease expired in 2019, and the company had been renting the space on a month-to-month basis since then. But the state filed an unlawful detainer in August against Apex, accusing the company of subleasing the property to at least five tenants without authorization and failing to pay more than $130,000 in back rent.
The governor said that in the wake of the fire, the state had launched a “deep dive analysis” of the thousands of public- and private-sector entities leasing space across the state from Caltrans, including at least four additional leases held by Apex. Revenue from the leases helps underwrite public transit in the state, the governor added.
The nearly two-mile stretch of freeway in Los Angeles is much busier than a section of Interstate 95 in northeast Philadelphia that partially collapsed after a fire in June, according to government data. In that instance, officials reopened the highway in less than two weeks, far sooner than the several months they had initially anticipated.
Kirsten Noyes contributed research.