A narcotics agency officer in Delhi, who has taken over six cases handled by Mumbai anti-drugs officer Sameer Wankhede, has earlier worked as Deputy Inspector General with the Central Bureau of Investigation. Sanjay Kumar Singh, a 1996-batch Odisha cadre Indian Police Service officer, will take over the six cases including the Mumbai drugs-on-cruise case. He is currently Deputy Director General (Operations) of the Narcotics Control Bureau or NCB.