PG&E Corp.’s chief executive said Monday that one of his company’s contractors doing work related to the 2018 Camp Fire aftermath had charged more than it was supposed to and inappropriately paid “large sums of money” to two PG&E employees.

The parent company of Pacific Gas and Electric Co. has canceled its contracts with the firm, Bay Area Concrete Recycling. And the two PG&E employees in question no longer work for the energy company, according to an internal message from PG&E Corp. CEO Bill Johnson that the company provided to The Chronicle.

Johnson said PG&E has also reported the situation to state regulators, local authorities and the court-appointed monitor who scrutinizes the company’s operations because of its probation from the 2010 San Bruno pipeline explosion.

Johnson indicated that the contractor did work associated with Butte County’s recovery from the 2018 Camp Fire, which was caused by a PG&E power line. PG&E spokesman Matt Nauman said in an email that the firm was “hauling and processing leftover soil that resulted from underground gas and electric construction projects.”

PG&E did not provide specifics about the contractor’s alleged “overbilling” or the “inappropriate payments and gifts” that Johnson said were given to the two employees. PG&E did not identify the employees.

Nauman said he could not share more information about what Johnson was referring to, citing the company’s ongoing investigation. The Chronicle reached out to Bay Area Concrete Recycling, which did not comment.

Regulators at the California Public Utilities Commission are looking into the matter, according to a commission spokeswoman.

Mark Toney, executive director of The Utility Reform Network consumer group, said in an email that the commission must figure out how much money was overbilled and should be returned to PG&E’s customers. Regulators need to shield customers from “paying for any additional work to replace inadequately done repairs, and take measures to hold PG&E management accountable for letting this corruption ... happen in the first place,” Toney said in his email.

In Johnson’s message, which was sent to PG&E’s entire 23,000-member workforce, he said the company had heard from its own employees and outside vendors “about possible fraud” and violations of the company’s code of conduct. A preliminary investigation found the contractor had charged too much and made the improper “payments and gifts” to two employees overseeing its work, Johnson said.

Johnson said PG&E had “terminated all contracts” with Bay Area Concrete Recycling. PG&E also “confronted the two PG&E employees supervising BAC with the evidence that they received large sums of money and gifts from the vendor,” he said. The employees are no longer with PG&E.

Johnson said PG&E had “already redirected the work to new vendors to make sure our efforts rebuilding in Paradise and Butte County will not be delayed.”

“I want to be clear, this is unacceptable behavior and does not live up to the high ethical standards we aspire to as individuals and as a company,” he said.

PG&E will share the final conclusions of its investigation with authorities, employees, customers, regulators and the court-appointed monitor, Johnson said.

J.D. Morris is a San Francisco Chronicle staff writer. Email: jd.morris@sfchronicle.com Twitter: @thejdmorris