He travelled from Mumbai to Dubai 78 times in a year but doesn?t have a permanent account number (PAN). Another person travelled to the same destination 31 times in a year but reports an annual business income of just R95,000. India?s tax sleuths have come across such puzzling data while unearthing primary financial information about Indians travelling to various tax havens.

Forget Liechtenstein, Panama, the Cayman Islands, Isle of Man or even Mauritius. Good old Dubai, home to free trade zones offering lavish tax sops, appears to be the preferred destination of resident Indians wanting to dupe the taxman.

With the government caught in a cleft stick over allegations of vast amounts of unaccounted cash stashed away in tax havens, the I-T department thought it worthwhile to track data of people visiting them. The department now has the details of Indians? trips to Dubai, Switzerland and Cayman Islands during 2009-10.

Overall, 19 persons have travelled to Dubai over 30 times by air during the year. The age of those who visited this destination range between 28 and 55 and most of them flew out from Mumbai to Dubai. FE has the names of these persons and passport numbers, among others.

?We are examining the details of these persons, looking at their sources of income and the tax returns filed by them. Any violation of tax norms would be dealt with seriously,? a finance ministry official told FE.

The ministry suspects that this tax haven is misused by investors for re-routing funds into India. ?We are looking if the Dubai route is being used for re-export of investments into India. UAE has become one of the largest re-export partners. A lot of the investments between India and Europe are routed through Dubai,? said another official.

Trips to Switzerland and Cayman Islands too were tracked. In 2009-10, over 13 lakh people visited any one of these places once, while 1.31 lakh people travelled twice to these destinations. Similarly, 30,127 persons visited these countries three times and over 10,000 people made air trips four times.

The I-T department, which has passport details of these persons, is also investigating their sources of income. Many of these frequent fliers were not available on the address provided in their passports. ?So far, we have not got any major breakthrough regarding tax evasion. However, we are examining the cases and are in touch with travel agents who have organised these trips to get more details of persons who are not traceable,? an official said.

The information gathered by the I-T department will also be useful for other law enforcement and investigating agencies, who could look into money-laundering and national security issues, among others. The department is also tracking data on travel to other tax havens to locate illegal funds.

Tax benefits provided by these countries have often been found to be misused by investors for re-routing funds, a technique known as round-tripping. On Saturday, Central Board of Direct Taxes chairman Prakash Chandra had said that India would hold discussions soon to renegotiate the double taxation avoidance agreement (DTAA) with Mauritius to plug such loopholes.

?Maximum round-tripping was happening from Mauritius. Dubai also offers similar tax benefits, since the treaty is similar,? Deloitte tax partner Vipul Jhaveri said. He added that I-T department?s recent initiatives will their investigations in this regard.

The Indian government is facing intense pressure from the civil society activists, opposition parties and the Supreme Court over allegations that large amounts of black money have been parked abroad by some Indians. India has revised DTAAs with 36 nations to enable sharing of banking and tax-related information. The revised tax treaty with Switzerland has enabled such data sharing since April 1, 2011. A Tax Information Exchange Agreement was signed with Cayman Islands in March this year.