The report, citing sources, said the Securities and Exchange Commission was looking into whether Arora, who was tipped as the next CEO, held conflicts of interest or engaged in questionable behavior before resigning from SoftBank last week.

SoftBank and Arora have described his departure as an amicable one, saying Masayoshi Son, chairman and chief executive of the company, recently decided he wanted to stay longer instead of handing over to Arora when turning 60 next year.

Earlier this year, a law firm saying it represented the interests of unidentified shareholders called on SoftBank to investigate whether Arora had conflicts of interest due to his role as a senior adviser to private equity firm Silver Lake.

Asked about the report on Thursday, a SoftBank spokesman referred to a company statement last week saying the allegations were without merit.

Arora was not immediately available to comment.

(Reporting by Yoshiyasu Shida; Editing by Stephen Coates)