NEW DELHI: Indian tax officials on Thursday left the BBC's offices in New Delhi and Mumbai, after a three-day inspection that involved the cloning of data from some digital devices, the tax department said.

The inspection came weeks after the government reacted angrily to a BBC documentary about Prime Minister Narendra Modi. The broadcaster, which said its operation in India had returned to normal, has called the situation stressful and disruptive.

A tax department spokesperson said investigators cloned data from digital devices considered important, but did not confiscate any.

They only recorded statements from employees whose roles were crucial, primarily staff from finance, content development and other production-related departments, the spokesperson said.

Two sources told Reuters earlier on Thursday that the tax officials examined mobile phones and laptops used by some BBC editorial and administrative staff.

A BBC spokesperson confirmed the tax officials had left the offices.

"We are supporting staff – some of whom have faced lengthy questioning or been required to stay overnight – and their welfare is our priority," the spokesperson said.

"Our output is back to normal and we remain committed to serving our audiences in India and beyond."

BBC staff were asked to stay off social media and report any adverse comments they received on such platforms, the broadcaster told employees in an internal memo sent on Thursday and seen by Reuters.

The BBC's Modi documentary raised questions over his role during deadly communal riots in Gujarat in 2002, when the Hindu nationalist leader was chief minister of the western state.

The government dismissed the documentary, "India: The Modi Question", as propaganda and blocked its streaming and sharing on social media.

The broadcaster has stood by its reporting, which investigated one of the worst outbreaks of religious violence in India in the modern era. At least 1,000 people, mostly Muslims, were killed in the bloodletting. Activists put the toll at more than twice that number.

The BBC has said that it was "fully co-operating" with the tax authorities, and an earlier internal memo instructed staff to answer questions honestly and "not delete or conceal any information on any of your devices."

A government official denied accusations that the tax survey was "vindictive", saying it was related to transfer pricing rules and alleged diversion of profits.

Kanchan Gupta, a senior adviser at the Ministry of Information & Broadcasting, told Times Now news channel on Wednesday that the BBC was served tax notices in the past but had not provided a "convincing response."

In recent years some international companies had come under the income tax scanner regarding transfer pricing rules, but several media organisations and rights' group criticised the ongoing search at the BBC.

"We demand that this intimidation be stopped and journalists are left to do their jobs without fear or favour," the Mumbai Press Club said in a statement.