Mumbai police on Thursday claimed to have busted a Television Rating Points (TRP) manipulation racket, adding four persons have been arrested in this case.Mumbai police commissioner Param Bir Singh told reporters that Republic TV, a national TV news channel facing flak over its attack on Mumbai police and Maharashtra government in the Sushant Singh Rajput death case, was involved in the racket #MumbaiPolicecommissionerparamvirsingh #RebublicTV