NEW DELHI: Bollywood's Amitabh Bachchan and martial arts movie star Jackie Chan are among celebrities who feature in a massive leak of documents, some of which reveal hidden offshore assets.

The Panama Papers, which are being described as the biggest leak in history, feature over 500 Indians linked to offshore firms, reported The Indian Express,, whose team was part of the eight-month long investigation spearheaded by the International Consortium of Investigative Journalists (ICIJ).

Out of the 11.5 million files, Indian reporters went through over 36,000. They discovered that over 500 Indians were complicit in paying Mossack Fonseca— a Panama-based law firm with offices in more than 35 countries— to buy the benefits of secretive, lax regulatory systems by setting up offshore entities.

They also found 234 Indian passports (handed over by clients as part of the incorporation process).

Complicating the leak is the fact that Indian citizens are not allowed to set up offshore companies under laws dictated by the Reserve Bank of India (RBI), The Indian Express has noted.

The paper has also published the names of notable Indians found in Fonseca's list of offshore companies, foundations and trusts, including real estate tycoons, top industrialists, sportspeople, businesspeople, politicians, and celebrities.

Bringing down the Bachchans

According to the leaked documents, Bollywood legend Bachchan— simply known as the 'Big B' in India— was appointed director of at least four shipping companies registered in offshore tax havens set up 23 years ago.

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The authorised capital of these companies ranged from just US$5,000 to US$50,000, but they traded in ships worth millions of dollars, according to The Indian Express.

Bachchan, who has long since resigned from the companies and has not commented on the documents, is not the only member of his famous family named in the leaks.

Actress Aishwarya Rai Bachchan, also Amitabh Bachchan's daughter-in-law, was also director and shareholder of an offshore company, along with members of her family, before it was thought to have been wound up in 2008, according to the newspaper.

The media adviser of the former Miss World winner has rejected the documents as “totally untrue and false”.

As with many of Fonseca's clients, there is no evidence that the Bollywood A-listers used their companies for improper purposes and having an offshore entity is not illegal.

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Modi responds

Prime Minister Narendra Modi's government has vowed to crack down on the “menace” of so-called black money— vast sums stashed abroad to keep them secret from Indian tax authorities.

Aside from the Bachchans, the list includes Indiabulls owner Sameer Gehlaut, DLF CEO KP Singh, and business tycoon Gautam Adani's elder brother Vinod.

Also read: Offshore accounts: What they are and how they are used

Hong Kong film star Jackie Chan has also been revealed to have at least six companies represented by Fonseca's firm, though he too may have used the companies legitimately for business purposes rather than for tax avoidance.

A global investigation

The Express is among more than 100 media groups which have investigated a massive leak of 11.5 million documents from the database of Mossack Fonseca, a Panama-based law firm with offices in 35 countries.

The stash of records was obtained from an anonymous source by German daily Sueddeutsche Zeitung and shared with media worldwide. The documents, from around 214,000 offshore entities, cover almost 40 years.

The papers made their way to Indian media through the International Consortium of Investigative Journalists (ICIJ), which contacted media groups worldwide to investigate its contents. The Indian Express agreed to be ICIJ's Indian partner.

In 2013, The Indian Express published a similar expose to the Panama Papers, titled "Offshore Leaks". The investigation named 612 Indians, including two politicians who were members of parliament and several top industrialists. That investigation set in motion an attempt at accountability, and several of these people received tax notices and were persecuted for their illegal entities.