The Sahara Group reportedly owns some luxury apartments and assets abroad apart from the three luxury hotels -- Grosvenor House Hotel in London, New York Plaza and Dream New York -- which were put up on sale to raise money needed to secure a bail for its chief Subrata Roy.

The other properties owned by the group include a fleet of luxury aircraft and two offshore accounts in Mauritius and Singapore run through its subsidiaries Aamby Valley (Mauritius) Ltd, according to the documents reviewed by Business Standard.

These assets "have escaped the attention of the Securities and Exchange Board of India (Sebi) and the Supreme Court," the report said.

Some of these properties are being "used" by Sahara chief Subrata Roy's elder son Sushanto Roy, said the report.

The total value of these undisclosed properties may be worth hundreds of crores, according to consultants.

A 2011 mortgage agreement between Sahara Grosvenor Hospitality (the holding company of Grosvenor House) and Bank of China showed that the group possessed "at least nine properties in prime localities in central London." Some of these properties were situated close to Buckingham Palace and the others near Grosvenor House.

"The properties belonged to certain subsidiaries of our international hospitality holding company in Mauritius, called Aamby Valley (Mauritius) Ltd. These properties have been leased to Sahara Grosvenor House Hospitality Ltd (which owns Grosvenor House Hotel). The said properties are used as a guest house-cum-office for the asset management of Grosvenor House Hotel and the Formula One set-up there," said a Sahara spokesperson.

OT Global Holdings, a subsidiary of Aamby Valley (Mauritius) Ltd, owns a fleet of five luxury aircraft, which includes three Embraer Legacy 650 aircrafts, Embraer Lineage 1000 and a Cessna Citation XLS.

The group's spokesperson has confirmed that the foreign bank accounts owned by the company are not individual accounts but in the name of a subsidiary of Aamby Valley (Mauritius) Ltd.

Sahara Group chief Subrata Roy has been behind bars since March 2014, following the group's failure to comply with a court order to return the money to investors it had raised through an illegal bond programme.

The apex court had ordered Roy to deposit Rs 10,000 crore to secure an interim bail. It asked him to pay half the amount in cash and the remaining as bank guarantee. The SC had also ordered the group to refund nearly Rs 36,000 crore to bond investor in nine instalments in the next 18 months.