Amit Jogi, former Chhattisgarh chief minister Ajit Jogi's son arrested in connection with the murder of a Nationalist Congress Party leader, was on Saturday sent for six days in the Central Bureau of Investigation's custody.

A Delhi court accepted the agency's plea that his interrogation was required to unearth the conspiracy behind the crime.

After hearing a two-hour argument, Metropolitan Magistrate V K Khanna remanded Amit till July 8, with the CBI seeking time to recover weapons and investigate money transactions.

The CBI, which plans to take Amit to Raipur, where the crime took place, and other parts of Chhattisgarh, also proposes to subject him to lie detector and other scientific tests. Terming Amit as the "mastermind of the murder" to eliminate NCP treasurer Ram Avtar Jaggi, the CBI claimed it had concrete evidence that the accused had full knowledge of the criminal conspiracy, involvement of various conspirators, arrangement of money for executing the plan and arrangement of weapon for the murder and the killers.

The CBI arrested Amit on Friday after he was questioned for five hours in connection with the murder two years ago.

The CBI had initially requested 14 days custody of the accused.

The defence fiercely opposed this saying there was nothing much to be investigated at this stage with all the co-accused arrested and most of the recoveries made.