Dalton Investments has demanded Fuji Media Holdings immediately establish a third-party committee to investigate facts related to alleged sexual misconduct committed by TV star Masahiro Nakai.

In a letter sent through its affiliate, Rising Sun Management, to Fuji’s board of directors on Tuesday, the U.S.-based investment management firm said it is “outraged” by the “serious flaws” in the broadcaster’s corporate governance in relation to its handling of the recent uproar sparked by Nakai, a former member of the now-defunct, hugely popular boy band SMAP. Dalton is a major shareholder of the Japanese media conglomerate.

According to media reports, Nakai made a large lump-sum payment to a woman in relation to “sexual troubles,” and that an executive of Fuji TV, a company under the Fuji Media group, had been involved in arranging a meeting between the two. Fuji TV has denied any involvement in the matter.