New Delhi, April 11: The Centre today justified in the Supreme Court its decision to curtail the original March 31, 2017, deadline for depositing demonetised notes to December 30, 2016, saying it was done to combat large-scale malpractices.

"From our side, the window period has come to an end on December 30," attorney-general Mukul Rohatgi told a bench headed by Chief Justice J.S. Khehar and submitted an affidavit explaining the curtailment.

However, the bench said it would examine in July the question of whether the period should be extended. It adjourned the matter, allowing some petitioners to file their response to the Centre's stand against extending the deadline beyond December 30, 2016.

Strictly speaking, since the original deadline of March 31 has also ended, the petitioners have sought an extension till June 30. However, the matter will now be heard only in July, though the court set no date.

Some PILs have challenged the curtailment of the period for depositing old Rs 500 and Rs 1,000 notes through an ordinance, describing the measure as illegal. The petitioners include individuals and business firms.

At the last hearing, the court had indicated that if it eventually finds the December 30 ordinance illegal, it would ask the government to consider the plea of the petitioners to accept their demonetised notes, if adequate reasons were given for not having deposited the money before December 30.

In its affidavit, the Centre said "there is no legal duty upon the government to issue any notification extending the grace period". It said various malpractices, including buying of gold, were reported after the November 8 demonetisation notification.

"Between 09.11.2016 and 10.01.2017 alone (which includes demonetisation period ie., 09.11.2016 to 30.12.2016), there were more than 1100 raids/surveys conducted by the income tax department on various persons. During the period, more than 5,100 notices were issued for verification of high-value suspicious cash deposits made in bank accounts," the government said in the affidavit.

Further, the Centre said preliminary investigations following the tax raids in the first three weeks after demonetisation revealed an unusual spurt of cash sales immediately after the announcement and cash dealswithout PAN in a large number of cases.

Other suspected malpractices included splitting of bills to hide the identity of the purchasers, backdating of sales, receipt of cash advances against future sales, and routing of money through shell companies and "intermediaries" before being sent to bullion traders' accounts, the affidavit said. There was also gross misuse of exemptions granted for use of old notes at petrol pumps, airline ticket offices, railway booking counters and toll plazas among others.

"As a result of the raids and other strict measures enforced, more than Rs 610 crore (including cash of Rs 513 crore, of which Rs 110 crore was in new currency) and valuables were seized. The undisclosed income detected in the above actions was more than Rs 5,400 crore," the government added.