The U.S. securities regulator is examining whether the state of California violated securities laws by failing to disclose the risks attached to its public pension fund, the New York Times reported, citing a person with knowledge of the investigation.

California Public Employees Retirement System, also known as Calpers, suffered steep losses during the financial meltdown. The value of the fund's assets had plunged to $160 billion from a peak of $260 billion in 2007, though they have since recovered to about $220 billion.

It is unclear whether investigators are focusing on the failure to disclose risks and the amount of money it might need to cover any shortfall or on any possible conflicts of interest in steering investments to related parties, the subject of a separate investigation by the attorney general of California, it said.

Securities and Exchange Commission officials declined to confirm an investigation to the New York Times. A spokeswoman for Calpers said it had not been contacted by the SEC about its accounting or about financial disclosures, the news daily said.

SEC and Calpers did not immediately respond to emails seeking comment by Reuters outside regular U.S. business hours.