Nissan has accused its former chairman Carlos Ghosn, first arrested on Nov. 19, of financial misconduct. Prosecutors have charged Nissan along with Ghosn for under-reporting his pay. Ghosn has denied the charges.

Bloomberg, citing sources, said the SEC is examining whether the company maintained adequate controls to prevent improper payments.

A Nissan spokesman confirmed the automaker received an inquiry from the US regulator, without giving further details. The SEC was not immediately available to comment on the matter.

Nissan shares were down 1.0 percent at 919 yen in mid-afternoon trade, compared with a 0.4 percent decline in the Nikkei average.