The Central Bureau of Investigation on Tuesday registered a 'preliminary enquiry' into the bribery charges against former Union minister of state for environment and forest Dilip Singh Judeo.

Judeo, widely believed to be the Bharatiya Janata Party's chief ministerial candidate in the November 20 election in Chhattisgarh, was caught on camera purportedly accepting a bribe.

CBI registered the PE after seeking legal opinion and the agency will now determine whether the VCD which showed Judeo accepting money from a contractor seeking mining rights in Chhattisgarh and Orissa was genuine or doctored, agency sources said.

CBI spokesman G Mohanty said a team has been constituted to look into the case.

When Mohanty was asked why a case of under the Prevention of Corruption Act was not registered, he said: "Don't underestimate the scope of the preliminary inquiry. It is more like a case being registered."

Deputy Prime Minister Lal Kishenchand Advani, while addressing a press conference in Raipur had said that the agency would unravel the conspiracy and the people behind it.

Asked if The Indian Express Editor-in-Chief Shekhar Gupta and the reporters who broke the story would be questioned too, he said: "We would be looking into all aspects of the incident."