Photo: CTV

California officials say they will seek more than $90 million in firefighting costs from Pacific Gas & Electric Co. after finding that a deadly 2015 fire was sparked by a tree that came into contact with a power line.

The California Department of Forestry and Fire Protection released a report Thursday detailing the cause of the fire in Calaveras and Amador counties.

The amount is believed to be the largest recovery amount ever sought by Cal Fire, said spokeswoman Janet Upton.

Cal Fire said the state's largest utility or its contractors had removed two grey pine trees from a stand in January 2015, exposing a weaker, skinnier interior tree.

The 44-foot-tall grey pine tree grew taller, seeking the sun, but eventually slumped into a power line, according to the report.

The blaze started Sept. 9 and burned for three weeks. It killed two people and destroyed more than 900 structures, including some 550 homes.

The fire caused an estimated $300 million in insured losses and is the seventh-most destructive wildfire in state history.

PG&E did not have immediate comment.