Sameer Wankhede, the Narcotics Control Bureau (NCB) officer leading the probe into the drugs case involving Shah Rukh Khan's son, Aryan Khan, reached Delhi on Monday evening but denied that he had been summoned by any agency.
At the airport, surrounded by reporters, Mr Wankhede said he is in the national capital for some work.
"I absolutely stand by my investigation, 100 per cent," he told NDTV.
Mr Wankhede's visit to Delhi comes amid the row over payback allegations and his war of words with Maharashtra minister and NCP leader Nawab Malik.
The NCB zonal director's name cropped up in the row over alleged paybacks following an affidavit by a witness in the case who claims to be the bodyguard of Kiran Gosavi, a private investigator whose selfie with Aryan Khan had thrown up many questions.
In an affidavit, Prabhakar Sail claimed that he had heard a conversation between Gosavi and one Sam D'Souza on October 3 about a Rs 18 crore deal. KP Gosavi said they will have to give Rs 8 crore to Sameer Wankhede, Mr Sail said in the affidavit.
The NCB has backed the officer, saying he has an "impeccable record".
Also, Mr Wankhede has been on the crosshairs of minister Nawab Malik who has alleged that the case relating to the alleged recovery of drugs from the cruise ship is "fake" and accused the BJP and NCB of spreading terrorism in Mumbai.
Mr Malik on Monday tweeted a photo of a document related to Mr Wankhede's birth and claimed, "the forgery began from here".
Hitting back, the officer said in a statement, "The publishing of my personal documents is defamatory in nature and an unnecessary invasion of my family privacy. It is intended to malign me, my family, my father, and my late mother."
He has said the minister's actions had put his family under "tremendous mental and emotional pressure".
In an affidavit submitted to the special court hearing the drugs-on-cruise case, he wrote: "... I have been personally targeted, especially by a known political figure, (since) one Sameer Khan, a relative of this honcho, was arrested in a drug case... from that time there is a personal vendetta targeted at me and my family members... was threatened to be arrested and dispelled from my job/service."