SAN FRANCISCO (AP) — California regulators on Tuesday called on Pacific Gas & Electric Co. to pay at least $300 million in fines in connection with a deadly 2010 gas pipeline blast in what they said would amount to the largest fine ever levied by the state Public Utilities Commission.

In an amended brief filed in the pipeline case, the commission's safety division cited the eight people killed and 38 homes destroyed in the blast in the San Francisco Bay area suburb of San Bruno and said there were steps PG&E could have taken to prevent the explosion.

Regulators had originally recommended no fine, calling instead on PG&E to spend $2.25 billion on pipeline safety improvements. In that case, the company would be able to claim a portion of the penalty as a tax deduction.

Under the amended brief, $300 million of that amount would go into the state's general fund in the form of a fine.

A call to PG&E for comment was not immediately returned.

The National Transportation Safety Board unanimously agreed in 2011 that the blast was caused by what board chairman Deborah Hersman called a "litany of failures" by PG&E, as well as weak oversight by regulators.

Separate from the NTSB investigation, investigators at the utilities commission blamed PG&E for the explosion, which occurred when an underground pipeline ruptured at the site of a decades-old faulty weld, sparking a massive fire.

PG&E has accepted liability for the disaster in numerous public statements but has denied most of state investigators' allegations that the utility violated safety rules.