The agency has alleged that Mr Kapur was employed by Group CEO of AirAsia Tony Fernandes as lobbying agent to whom the onboard catering contract was given by Deputy CEO Bo Lingam as a "quid pro quo" without any negotiation.
The sources said Mr Kapur was called at the agency headquarters where he was questioned on various aspects of his relationship with AirAsia and meetings with its executives.
He was also asked about the meetings of civil aviation ministry officials and AirAsia executives arranged by him, the sources said but refused to give specific details as it may reveal the identity of the ministry officials under CBI scanner in the matter thus adversely affecting the probe.
The agency officials also asked him about the alleged role of one Sriram who had purportedly received Rs 50 lakh from Bo Lingam for diluting 5/20 rule for international operations licenses.
The CBI has alleged that in December, 2014, at the coffee shop in the Four Seasons Hotel, Mumbai, Mr Kapur along with Bo Lingam had handed over a closed packet containing Rs 50 lakh in cash to Sriram to facilitate the removal of the 5/20 rule.
"An effort was allegedly made in the Ministry of Civil Aviation to remove/amend the 5/20 rule (which makes it mandatory for an airline to have five years of flying experience and 20 aircraft to be eligible for international flying licence)," CBI Spokesperson R K Gaur had said.
The CBI has booked Mr Fernandes, Bo Lingam, the then Deputy Group CEO of Malaysia based Air Asia Berhad and R Venkataramanan, Director of the Air Asia India Ltd, Bengaluru besides alleged lobbyists Kapur, Rajender Dubey and Deepak Talwar in the case.
The agency has summoned Mr Fernandes to tomorrow appear before it in the case.
After the registration of the FIR, CBI spokesperson R K Gaur had said the accused promoters of the company and board of directors allegedly entered in criminal conspiracy with unidentified government officials through lobbyists to expedite the approval process for AirAsia India and change in aviation policies to suit the company.
"It was further alleged that FIPB and FDI norms were violated by said air group by giving effective management control to a foreign entity by making the said private airline (Air Asia India Ltd) a de-facto subsidiary indirectly rather than a joint venture," Mr Gaur had said.
He had said lobbyists were allegedly paid money which was utilised for paying bribe to unknown public servants and others for securing permit for operation of international scheduled air transport services.
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