The Income Tax department survey operation against the BBC India continued for the second day with the sleuths understood to be making copies of electronic and paper-based financial data of the organisation, officials said Wednesday.

The tax department had launched the action on Tuesday at the BBC's Delhi and Mumbai offices along with at least two linked premises as part of an investigation into alleged tax evasion against the British broadcaster in India.

Sleuths knocked at the doors of the BBC around 11:30 AM on Tuesday and they are still present, sources aware of the development told PTI.

The tax officials are speaking to staffers of the BBC in the finance and some other departments even as other staffers and journalists were allowed to leave Tuesday night.

Some computer peripherals and mobile phones were cloned as part of the operation, officials had said.

The action, which sparked a sharp political debate with the ruling BJP accusing the BBC of "venomous reporting" and the opposition questioning the timing of the move, came weeks after the broadcaster aired a two-part documentary, "India: The Modi Question", on the prime minister and the 2002 Gujarat riots.

The survey is being carried out to investigate issues related to international taxation and transfer pricing of BBC subsidiary companies, officials had said on Tuesday.

While there has been no official statement from the Income Tax department on the action, the British Broadcasting Corporation (BBC) has said it was cooperating with the authorities.

"The Income Tax Authorities remain at the BBC offices in New Delhi and Mumbai. Many staff have now left the building, but some have been asked to remain and are continuing to cooperate with the ongoing enquiries," a BBC News Press Team said in a official Twitter post at 10:26 pm on Tuesday.

We are supporting our staff during this time and continue to hope to have this situation resolved as soon as possible. Our output and journalism continues as normal and we are committed to serving our audiences in India, the post added.

As part of a survey, the Income Tax department only covers the business premises of a company and does not raid residences and other locations of its promoters or directors.

The Supreme Court last week dismissed a plea seeking the imposition of a complete ban on the BBC in India in the wake of the controversial documentary, terming the petition "entirely misconceived" and "absolutely meritless".

Another set of petitions challenging the government's decision to block the documentary will be heard in April next. On January 21, the government issued directions to block multiple YouTube videos and Twitter posts sharing links to the documentary.