Some of the crucial documents which could throw light on Commonwealth Games deals have gone missing with the probe agencies fearing that they could have been destroyed or hidden.

Official sources said that the key files, which contain important information on tendering, budgetary allocation and contract details, are missing from the Commonwealth Games organising committee (OC) office.

They said that central bureau of investigation (CBI) officials have found sufficient evidence of criminal conspiracy by unknown OC officials in tampering with some documents and manipulating information in them.

The sources said that CBI officials have made a list of documents which are untraceable.

The revelation came during a series of searches carried out by a team of 20-30 sleuths at OC office besides its secretary general Lalit Bhanot's residence last month, they said.

The sources said that CBI sleuths were not getting cooperation of certain OC officials as their bosses -- OC chairman Suresh Kalmadi and Bhanot-- were still at the helm of affairs.

Hence, the CBI had conveyed to the government that continuance of Kalmadi and Bhanot in their posts was proving to be a stumbling block for its ongoing probe.

However, cabinet secretary K M Chandrasekhar is understood to have told the CBI that since the OC is no more a part of his secretariat he cannot remove Kalmadi and Bhanot.

The CBI will now approach sports ministry for their removal for smooth progress of the probe.

The central vigilance commission (CVC) is also probing alleged financial irregularities in the conduct of the mega sporting event by organising committee among others in October this year.

The comptroller and auditor general (CAG) too is looking into the accounts of the OC and various other projects associated with the probe.

The CBI has filed three FIRs in connection with the alleged irregularities in CWG and searched the residences of OC director general V K Verma and Bhanot on November 30.

While one case is related to a Rs 107-crore deal struck with a Swiss score keeping firm, the agency had earlier filed two FIRs for the contracting of AM Films and cars/vans for the Baton Relay ceremonies by the OC in London. It had arrested joint director general T S Darbari and deputy director general Sanjay Mohindroo for their alleged complicity in these deals.