US power company charged over deadly California forest fire
The Zogg Fire burned 56,000 acres and killed four people after it was sparked by a power line in September 2020(AFP)

A US power company whose cables sparked a devastating California fire that killed four people has been charged with manslaughter, prosecutors said Friday.

More than 56,000 acres (22,000 hectares) were set ablaze when power lines operated by Pacific Gas and Electric (PG&E) came into contact with a tree in September 2020, igniting what became known as the Zogg Fire.

Prosecutors said the company knew the tree in Shasta County was dangerously close to a powerline and should have removed it three years earlier.

"We have sufficient evidence to prove beyond a reasonable doubt that the Pacific Gas and Electric Company is criminally liable for their reckless ignition of the Zogg Fire and the deaths and destruction that it caused," the county's district attorney Stephanie Bridgett said.

"Their failure was reckless and was criminally negligent, and it resulted in the death of four people" including an eight-year-old girl.

The county also levelled charges over three other fires.

PG&E is one of California's biggest power companies, and is responsible for maintaining large swathes of the state's creaking electricity infrastructure.

That includes keeping trees away from powerlines, especially at a time when the region is suffering through a prolonged drought that has left its forests dry and vulnerable to wildfires.

The company on Friday denied it was criminally culpable for the blaze.

"We've accepted (the fire department's) determination, reached earlier this year, that a tree contacted our electric line and started the Zogg Fire. But we did not commit a crime," said chief executive Patti Poppe.

"We've already resolved many victim claims arising from the Zogg Fire... and we are working hard to resolve the remaining claims."

PG&E has already been found guilty of causing the Camp Fire in 2018, the deadliest fire in recent California history.

That fire virtually wiped the small town of Paradise off the map and killed 86 people.

This year the company said it would bury 10,000 miles (16,000 kilometers) of powerlines in an effort to keep them away from vegetation.

The western United States is suffering through yet another terrible wildfire season.

Scientists say human-caused global warming is making the region hotter, drier and more vulnerable to fire.