LOS ANGELES — The Securities and Exchange Commission has opened an investigation into Pacific Gas and Electric’s accounting for its losses related to three years of wildfires in Northern California, the utility reported to shareholders Thursday.

PG&E told investors that it learned in March that investigators from the S.E.C.’s San Francisco regional office had begun the review of public disclosures and accounting by the utility and its parent corporation for the 2015 Butte Fire as well as wildfires in 2017 and 2018. The fires killed scores of people, and the Camp Fire, which destroyed the town of Paradise last year, was the most destructive wildfire in California history.

The review is the latest in a series of federal and state investigations into PG&E’s finances, operations and safety culture.

PG&E, California’s largest utility, with 16 million customers, was convicted of six felonies after a 2010 gas pipeline explosion killed eight people and devastated a neighborhood in San Bruno in the Bay Area. A Federal District Court judge has been conducting hearings on PG&E’s operations after state regulators determined that the company had violated its probation by falsifying reports about its gas operations since the explosion.