A drugs case involving Maharashtra minister Nawab Malik's son-in-law was among six transferred out of the Narcotics Control Bureau's Mumbai unit on Friday evening, and handed to a special investigation team to be led by senior police officer Sanjay Singh.
The cases were transferred after extortion allegations against the agency's zonal director, Sameer Wankhede, who was heading the six investigations, including that into the Aryan Khan drugs case.
Sources said the SIT now intends to move the court to cancel bail granted to Mr Malik's son-in-law, Sameer Khan - a move almost certain to spark further political controversy given the minister has been relentless in his attacks on the anti-drugs agency and Mr Wankhede.
The decision to challenge bail was first made early last month, news agency ANI reported.
Sameer Khan had been summoned after the NCB found evidence of transactions worth Rs 20,000 with an accused in another drugs case. He was arrested in January - over 200 kg of what the agency said were drugs, but Mr Malik claimed was "herbal tobacco" - and granted bail in September.
His case was thrust back in the spotlight after the NCB last month arrested Aryan Khan, Bollywood star Shah Rukh Khan's son, in connection with the drugs-on-cruise case.
Mr Malik began attacks aimed at the agency and Mr Wankhede, whom he accused of extortion of Bollywood stars, forging a caste certificate, and arranging a "fake" case to entrap SRK.
He has also accused the agency of trying to discredit the image of Bollywood and Maharashtra.
Most recently he shared unverified WhatsApp chats between Mr Wankhede's sister and a known drug smuggler. Mr Malik said the conversation was proof of a "private army" led by the NCB officer that was trapping and extorting money from actors.
Mr Wankhede said the chats were part of several in which his sister, Yasmeen Wankhede, a lawyer, rejected an approach for representation because she did not handle drug cases.
The agency and Mr Wankhede, as well as his sister, have hit back by accusing Mr Malik of a "personal vendetta" and concocting tales to malign the NCB's image.
Last week Mr Wankhede, who has also been accused of a Rs 8 crore payoff in connection with the Aryan Khan case, filed an affidavit saying he was being targeted by "a known political figure, (since) one Sameer Khan, a relative of this honcho, was arrested in a drug case".
"The publishing of personal documents (a birth certificate) is defamatory... unnecessary invasion of my privacy... intended to malign me, my family..." Mr Wankhede also said, referring to attacks by Mr Malik that say the officer lied about his background to secure a government job.
Mr Malik responded to that charge by declaring that the agency was "hiding" behind his son-in-law's case to deflect attention from, and scrutiny of, its handling of these cases.
The agency and officer have stood by each other and their investigations into Sameer Khan and the Aryan Khan case, but an internal inquiry has been opened against Mr Wankhede, from whose team the two cases (and four others) have now been removed.
Mr Wankhede has said the transfer of cases was at his request, and the agency has stressed that - contrary to rumours - no officer has been removed from his/her post at this time.
With input from ANI