The Narcotics Control Bureau (NCB) has suspended two of its Mumbai zone officers, superintendent V V Singh and intelligence officer Ashish Ranjan Prasad, for alleged "dereliction of duty" in investigations conducted by them, officials said on Wednesday.

The two officers also investigated the cruise drugs case in which at least 20 people, including actor Shah Rukh Khan's son Aryan Khan, were arrested in October inMumbai. Singh was the investigating officer of the case and Prasad his deputy.