The supreme court on Monday flayed the government for not probing into specific sources of black money stashed in banks abroad and asked the centre to apprise it of its investigation into the threat to national security posed by it.

The apex court also expressed its dismay that the government's probe into the issue of black money was focussed only on the case involving Pune stud owner Hasan Ali Khan and no name of any other person involved in stashing funds abroad has come out.

"No further information is coming out. Only one individual is there. What about others?" a bench of justices B Sudershan Reddy and S S Nijjar asked solicitor general Gopal Subramanium, who submitted to the bench, in a sealed cover, the enforcement directorate's status report of its probe in the case.

After perusing the status report, the bench criticised the steps taken by the government in the investigation of the matter including that relating to the passport case against Khan.

"It is very difficult to be calm and quiet after seeing the status report," the bench remarked.

"Why all these agencies were sleeping since 2008? Why it moved when we stepped in? If writ petition had not been filed, nothing would have happened," the bench observed.

The court was hearing a PIL seeking retrieval of black money stashed by Indian citizens in banks abroad. The PIL had been filed by former union law minister Ram Jethmalani.

The court reiterated its idea of setting up a special investigation team (SIT) comprising officers of intelligence bureau, research and analysis wing, central bureau of investigation and enforcement directorate to probe the entire issue related to the black money stashed in banks abroad.

The solicitor general said the investigation into the matter has revealed the involvement of a "power broker" in it and sought to assure the court that substantial progress has been made into the investigation of the case involving Khan.

He said the case concerning Khan was not simply a case of forgery of passport but a case with far more serious implications.

Subramanium said the ED has taken serious note of Khan's repeated statement seeking protection to his life and to his family members.

The law officer said there was need for protection to all the officers investigating the case rather.

During the last hearing on March 18 too, the apex court had toyed with the idea of forming a special investigation team (SIT) to probe the malady of Indian black money stashed in banks abroad and had asked the centre to come up with its take on possible composition of the SIT.

"In principle, do you have any objection to setting up of SIT to look into the matter?" the bench had asked the government, while observing, "We are not talking about one case but many cases are involved in it. This is much wider."

It had told the centre and the petitioners to respond on the next date of hearing about its stand and the possible composition of the SIT.