With the upscale Adarsh co-operative housing society coming under a cloud, the CBI has stepped in and is probing how prime defence land here was transferred to it and set a one-week deadline for the society to provide relevant documents.

Chief Minister Ashok Chavan's link to the society has also emerged with revenue and society officials saying his late mother-in-law Bhagwati Manoharlal Sharma figured in the list of its members.

Chavan was not available for comment but he has sought information on the Adarsh controversy.

The CBI is also investigating how the beneficiaries, including former services chiefs, politicians and bureaucrats, raised money to buy apartments meant for Kargil war heroes and their families in the posh Colaba area in South Mumbai.

The agency, which had begun its probe into the row in early October, has sought documents relating to the society. Former Army chiefs Generals N C Vij and Deepak Kapoor, ex-Navy chief Admiral Madhavendra Singh, former Army Vice Chief Lt Gen Shantanu Chowdhary, former Union Minister and Shiv Sena MP Suresh Prabhu are among those who have been alloted flats in the 31-storey building.

"We had sought all documents pertaining to the society from the city collector, society's general secretary and authorities of the Indian Navy and Army in early October," a senior CBI official said today.

"While we have received around 4,000-page documents from the collector's office, there has been no response from the other concerned agencies," the official said. The documents were sought following a specific complaint of irregularities, the official said, adding a deadline of one week has been given to the society today to submit the documents failing which the agency would proceed with the investigation in accordance with law.

The housing society, built on prime defence land, has been constructed in alleged violation of rules. The building was originally meant to be a six-storey structure to house Kargil war heroes and widows. "We are going through the documents provided by the collector's office and further course of action would be decided later," the official said.

The agency is trying to ascertain how the defence land was transferred to co-operative housing society and how the beneficiaries, including government servants, raised money to buy the apartments. "A 1,000-square foot apartment in the society would have cost around Rs 70 lakh in 2004. We will find out how individual beneficiaries arranged the funds," the official said.

The Army yesterday said it was carrying out an inquiry into Mumbai's Adarsh Co-operative Housing Society row. "As far as we are concerned, the inquiry is on and I would not like to comment beyond this as it may hamper the inquiry," Army chief General V K Singh had said yesterday.

Defence Minister A K Antony had said the government was 'seriously examining' the matter. The Navy has objected to Maharashtra government according permission for Occupation Certificate citing serious security concerns.

The 100-metre tall building next to a planned helipad and military installations has violated the CRZ limit of a height of 30 metres, the Navy had said.