SAN FRANCISCO (AP) - Regulators are accusing one of California's largest utilities of falsifying safety documents on natural gas pipelines over a five-year period.

The California Public Utilities Commission said Friday that an investigation by its staff found Pacific Gas & Electric Co. lacked enough employees to fulfill requests to find and mark natural gas pipelines.

Regulators say that because of the staff shortage, PG&E pressured supervisors and locators to complete the work, leading staff to falsify data from 2012 to 2017.

A U.S. judge fined the utility $3 million after it was convicted of six felony charges for failing to properly maintain a natural gas pipeline that exploded south of San Francisco in 2010, killing eight people.

PG&E didn't immediately respond to a request for comment.