(Bloomberg) -- PG&E Corp. shares tumbled after the company said it has fully drawn down revolving credit facilities, raising the specter of bankruptcy as wildfire losses grow.

The parent company and its utility subsidiary now have a total of $3.46 billion in cash and cash equivalents after drawing down revolving credit facilities, according to a regulatory filing Tuesday. Damages from the deadly Northern California wildfire may reach as much as $15 billion, Citigroup Inc. analyst Praful Mehta wrote in a research note Wednesday.

“The risk of bankruptcy is very real for these guys,” Bloomberg Intelligence analyst Jaimin Patel said in an interview. “With each passing wildfire, that risk increases.”

The company did not immediately return a call seeking comment.

Shares fell as much as 18 percent. It’s the fifth consecutive day of declines for San Francisco-based PG&E, which has lost 43 percent of its value since the Camp Fire broke out Nov. 8.

California authorities are investigating PG&E equipment as a possible cause of the Camp fire, the deadliest blaze in state history, burning about 150 miles (240 kilometers) northeast of San Francisco. It has killed at least 48 people, destroyed 130,000 acres and wiped out the town of Paradise.

PG&E said in its filing Tuesday that it has $1.4 billion in wildfire insurance coverage. “The utility could be subject to significant liability in excess of insurance coverage,” the company said.

PG&E already faces up to $17.3 billion in potential liabilities for 2017’s wildfires, according to a JPMorgan Chase & Co. estimate.

California enacted a law earlier this year to help utilities cover costs of last year’s, including by selling bonds backed by customer bills. But the measure didn’t specifically address how to handle the costs of any fires in 2018. So PG&E may need to turn to lawmakers for another fix.

“We think Sacramento will likely step in to protect the utility and its customers,” Citigroup’s Mehta wrote.

(Updates with analyst comment in third paragraph.)

--With assistance from Molly Smith and Joshua Fineman.

To contact the reporter on this story: Jim Efstathiou Jr. in New York at jefstathiou@bloomberg.net

To contact the editors responsible for this story: Joe Ryan at jryan173@bloomberg.net, Will Wade

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