New Delhi/Mumbai, March 4 (PTI): The Enforcement directorate (ED) has asked airport authorities to watch out for Hasan Ali Khan, the stud farm owner accused of stashing away $8bn (Rs 36,000 crore approximately) in Swiss bank accounts.

Sources said the financial crime watchdog issued the circular to prevent the Pune-based businessman from fleeing the country before investigations into his wealth begin. Khan is likely to appear before the directorate on March 7, they said.

The directorate recently sent a notice to Khan, who is under investigation for money laundering and for allegedly transferring cash/valuable assets outside the country by unlawful means with the help of foreign nationals.

In 2009, Khan was handed a tax bill amounting to nearly Rs 40,000 crore.

The Supreme Court, while blaming the Centre yesterday for not having the “will power” to act against black money hoarders, asked why Khan and others were not subjected to custodial interrogation though probe agencies had sufficient material.

“What the hell is going on in this country?” an anguished court had asked.

On February 11, the Supreme Court had asked the Centre to ensure that Khan did not leave the country in connection with the black money case.

Sources also indicated that Khan and his associates would be summoned for a new round of questioning by a joint team of law-enforcement agencies — the income tax department and the economic offences wing of the Maharashtra government.

Earlier, the directorate office in Mumbai had issued a nationwide alert in connection with Khan’s dealings to obtain information about his investments and transactions in the country.

The ED, the income tax department and the economic offences wing of Maharashtra are probing the illegal investments and charges of money laundering against Khan.

The directorate also wants to obtain all possible information from various state and central law enforcement agencies about the finances of Khan in its probe to track his money trail, sources said.

Khan had appeared before income tax authorities in Mumbai on February 18, apparently in connection with notices issued to him over the alleged tax evasion.

Tax enforcement agencies are now trying to locate Khan’s properties abroad that could be seized and auctioned to extract the tax liability.

In January 2007, the income tax department had raided Khan’s residence at Koregaon Park in Pune, along with properties in Mumbai and Hyderabad. The department also seized documents that showed he had $8.04 billion in a UBS account in Zurich. But the bank denied any business relationship with Khan.