CNN  — 

A 2017 fire in California that killed 22 people and destroyed more than 5,600 structures was caused by a private electrical system adjacent to a home, California fire officials said Thursday.

Investigators found no violations of state law or code related to the cause of the Tubbs Fire, said a press release from Cal Fire, the state’s forestry and fire protection agency.

Pacific Gas and Electric Co., though found not liable for the Tubbs Fire, has been linked to 17 others in 2017, California Gov. Gavin Newsom said Thursday.

“My focus is not PG&E, my focus is on California and Californians,” Newsom said. “My focus is on safe, reliable, and affordable service.”

PG&E shares spiked on the news.

The utility might still be on the hook for damages from last year’s Camp Fire, the most destructive wildfire in state history. Reports on the Camp Fire are expected to be released soon. PG&E has said it plans to file for bankruptcy because of potential claims in the tens of billions of dollars.

“Regardless of today’s announcement, PG&E still faces extensive litigation, significant potential liabilities and a deteriorating financial situation,” PG&E said.

The Tubbs Fire started in Sonoma County on October 8, 2017, burning 36,807 acres and destroying 5,636 structures, Cal Fire said.

It was part of a “fire siege” that month. More than 170 blazes burned at least 245,000 acres in Northern California, Cal Fire said. About 11,000 firefighters from 17 states and Australia helped battle the blazes.

CNN’s Paul R. La Monica contributed to this report.