SAN FRANCISCO (CBS SF) — The Zogg wildfire, which roared through the Shasta County communities of Igo and Ono last fall and claimed four lives, was triggered by a tree coming in contact with PG&E transmission lines, Cal Fire officials announced Monday.

The fire was first reported at 2:51 p.m. on September 27 and overnight grew from 100 to 7,000 acres. Before the flames were extinguished, the fire burned 56,338 acres, destroying 204 buildings and claiming four lives of Igo residents.

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The Zogg wildfire was among dozens that raged in the fall throughout Northern California. By the time the historic 2020 fire season came to an end, more than two million acres had burned — 3,125 square miles — nearly three times the size of Chicago, Manhattan and Los Angeles combined.

“Cal Fire investigators were immediately dispatched to the Zogg Fire and began working to determine the origin and cause of the fire,” the state agency said in a news release. “After a meticulous and thorough investigation, Cal Fire has determined that the Zogg Fire was caused by a pine tree contacting electrical transmission lines owned and operated by Pacific Gas & Electric located north of the community of Igo.”

The investigators have sent their report to the Shasta County District Attorney’s Office.