(Reuters) -U.S. regulators are investigating Massachusetts Mutual Life Insurance over its accounting practices in investment operations, the Wall Street Journal reported on Wednesday.

The Securities and Exchange Commission has issued subpoenas seeking information about MassMutual's bookkeeping around income on billions of dollars of loans it holds in its general investment account, the report said, citing people familiar with the matter.

According to the Journal, the SEC is investigating whether MassMutual properly reconciled accrued interest as it received payments on loans held in its general investment account.

The probe is ongoing and may not lead to formal allegations of wrongdoing, WSJ said.

MassMutual did not immediately respond to a Reuters request for comment.

Founded in 1851, Massachusetts Mutual Life Insurance is a mutual insurer offering life insurance, retirement and investment products.

MassMutual is a policyholder-owned company with no publicly traded shares. It regularly issues corporate notes and other debt securities, which are held by a broad range of investors who rely on its financial disclosures for investment decisions.