Amit arrived at the CBI headquarters in response to a notice issued by the agency asking him to appear for questioning in the case.
Accompanied by a lawyer, 27-year-old Amit was quizzed by sleuths of special crime unit of CBI for five hours before he was placed under arrest.
Highly-placed agency sources said CBI required Amitâ€™s custodial interrogation to unravel the conspiracy in the case. He has been charged with murder and criminal conspiracy.
Amit, who had failed to appear before CBI earlier, would be produced before a court here tomorrow for transit remand as he has to be produced before a designated court in Raipur.
CBI has so far arrested 14 people in connection with the case. Some of those arrested are former NSUI office bearers and are allegedly close to Amit.
Jaggi was shot dead on June four, 2003, a murder which had created a political storm in Chhattisgarh. The case was subsequently handed over to CBI.