State fire officials said the first blaze, which erupted between Tuesday and Thursday, was caused by a spark from malfunctioning construction equipment. But it could take months to get to the bottom of the most damaging fires.
Alberto Serrato pleaded not guilty to arson in connection with one of the smaller fires — a 105-acre fire in suburban Oceanside, which started Wednesday and is now fully contained. Bail was set at $250,000.
Tanya Sierra, a spokeswoman for the San Diego County district attorney’s office, said Serrato wasn’t seen igniting a fire but witnesses saw him adding dead brush onto smoldering bushes that flamed up. He has not been connected to any other fire, Sierra said.
Serrato was booked into jail Wednesday, according to the San Diego County Sheriff’s Department website, but his arrest wasn’t announced until Friday. Sierra didn’t know if he had an attorney.
All together, the wildfires have raced through an estimated 20,000 acres about 30 miles north of San Diego, causing more than $20 million in damage. One burned body was found in a homeless camp. At least eight houses and an 18-unit condominium complex were destroyed, and tens of thousands of people were warned to leave their homes.
Eight of the blazes popped up between late morning and sundown Wednesday, raising suspicions some had been set.
The region has become a tinder box in recent days because of conditions not normally seen until late summer — extremely dry weather, 50 mph Santa Ana winds and temperatures in the 90s. On Friday, though, cooler weather aided the 2,600 firefighters, and thousands of people began returning home.
In one of the hardest-hit cities, Carlsbad, investigators finished examining the burn site across the street from a park and focused on interviewing people who called a hotline set up to report any suspicious activity.
“Do people have suspicions? Yes,” said police Capt. Neil Gallucci, noting there has been no lightning to explain the blazes. “But can we confirm them? The answer is no.”
Police in the city of Escondido arrested two people, ages 17 and 19, for investigation of arson in connection with two small fires extinguished within minutes. But they found no evidence linking the suspects to the 10 bigger wildfires.
The list of possible causes is long.
“Our investigation might be over quickly for some of these fires — say, if we find a piece of metal nearby from a catalytic converter that backfired,” the sheriff said. “But others might not be so easy to determine. We’ll be talking to people in the areas to see if they saw anything to see if arson might have had a role.”