SEOUL, South Korea (AP) — South Korean prosecutors on Friday rejected a police request for an arrest warrant for music tycoon Bang Si-Hyuk, chairman of the agency behind K-pop supergroup BTS, questioning whether detention is necessary as he faces a high-profile investigation into alleged investor fraud.

The Seoul Metropolitan Police Agency asked prosecutors earlier this week to request a court warrant to arrest Bang, the billionaire founder and chairman of Hybe. The Seoul Southern District Prosecutors’ Office said that it found that the request lacked sufficient grounds to justify his detention and instructed police investigators to strengthen their case.

Bang, who has been barred from leaving the country since August, isn't seen as a realistic threat to flee.

The 53-year-old is being investigated over allegations that he misled investors in 2019 by indicating that Hybe had no immediate plans to go public, prompting them to sell their shares to a private equity fund, shortly before the company proceeded with an initial public offering.

Police believe that the fund may have paid Bang somewhere around 200 billion won ($135 million) in a side deal that promised him 30% of post-IPO stock sale profits.

Bang denies any wrongdoing, Hybe officials say. Bang’s legal team had criticized police for seeking his arrest, saying that he has been fully cooperating with the investigation for months.

Bang’s legal troubles are a public relations setback for Hybe, coming as BTS launches a global tour after a nearly four-year hiatus as its seven members served their mandatory military service.

BTS performed in front of tens of thousands of international fans at a free comeback concert in Seoul last month and have also held concerts in South Korea’s Goyang city and Tokyo. The group will kick off a series of U.S. events with a concert in Tampa, Florida, over the weekend.