Bang Si-hyuk is the founder and chairman of Hybe and the man behind BTS. (Credit: @hitmanb72/Instagram) South Korean prosecutors on Friday rejected a police request to arrest Bang Si-hyuk, the 53-year-old billionaire founder and chairman of Hybe, the entertainment company behind K-pop supergroup BTS , saying investigators had not yet built a strong enough case to justify his detention. The Seoul Southern District Prosecutors’ Office returned the arrest warrant request to police, saying it was filed on charges of fraudulent unfair trading under the Capital Markets Act. “At this stage, there is insufficient evidence to justify the necessity of detention, and we have therefore requested a supplementary investigation,” the prosecution said. The Financial Crime Investigation Division of the Seoul Metropolitan Police Agency had applied for the arrest warrant on Tuesday on charges of fraudulent and unfair trading.…