A Special Investigation Team (SIT) of the Narcotics Control Bureau (NCB) reached Mumbai on Saturday, a day after the agency transferred investigation in six cases, including the controversial cruise drugs case in which Shah Rukh Khan's son Aryan Khan was arrested.

The team, which flew in from Delhi later left for the NCB zonal office in south Mumbai, an official said. It is headed by senior IPS officer Sanjay Kumar Singh, DDG Operations at NCB headquarters.

The team will investigate the six cases, which have national and international ramifications in order to conduct deeper investigation to find out forward and backward linkages, the NCB said on Friday.

NCB zonal director Sameer Wankhede said he was not an investigating officer of these cases, adding he was a supervisory officer as a zonal director and his role will continue to be the same.

Meanwhile, NCP leader Nawab Malik on Saturday tweeted, "Skeletons will tumble out in the probe. I had demanded an S.I.T probe to investigate Sameer Dawood Wankhede for the kidnapping of & ransom demand from Aryan Khan. Now 2 SITs are constituted (state & centre), let us see who brings out the skeletons from the closet of Wankhede and exposes him and his nefarious private army."