The NCB SIT has found "grave irregularities" and gaps in the probe of the Mumbai drugs-on-cruise case with officials saying its first team that arrested Bollywood superstar Shah Rukh Khan`s son Aryan did not follow rules like mandatory medical test of accused, video recording of the raids and corroborate evidence for WhatsApp chats.

NCB director-general (DG) S N Pradhan told reporters that there were "shortcomings" in the investigation and WhatsApp chat of accused had no "physical corroborative evidence" as required to prove the charges in the court.