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PG&E Corp. (PCG - Get Report) soared as much as 80.6% Thursday after the California Department of Forestry and Fire Protection said the utility wasn't responsible for causing the deadly Tubbs Fire in 2017 -- one of two blazes that threaten to sink the utility with lawsuits.

Shares rose as much as $6.47 to $14.50 before PG&E trimmed its gains to close at $13.95, up 80.6% from Wednesday's finish. The New York Stock Exchange halted trading in the name for six minutes shortly after the news came out as part of a "volatility trading pause."

In a statement, the forestry agency said the Tubbs Fire "was caused by a private electrical system adjacent to a residential structure. CAL FIRE investigators did not identify any violations of state law, Public Resources Code, related to the cause of this fire."

Twenty-two people died in the October 2017 Tubbs fire about 70 miles north of San Francisco. The blaze burned nearly 60 square miles and destroyed more than 5,000 homes and buildings.

Earlier this month, PG&E announced plans to file Chapter 11 bankruptcy because it faces billions of dollars in potential liabilities in connection with the Tubbs Fire and another even deadlier blaze in 2018 that killed more than 80 people and destroyed Paradise, Calif. The cause of that fire remains under investigation.

A source told Reuters on Thursday that the news about the Tubbs fire doesn't change the company's plan to seek bankruptcy protection.

(This article has been updated.)