The serpent king (Nagaraja) idol dates back to the 6th or 8th Century and is believed to be from Rajasthan or Madhya Pradesh. The 'Dwarapalas' from Tamil Nadu is said to be from the 15th century.
The artefacts include centuries-old stone sculptures, idols, stone pillars, wooden artefacts, 'Vahanas' or ritual vehicles, and other antiquities. They have been lying in the premises of CBI-CID's Economic Offences Wing in Chennai.
The state government and Pon Manickavel have been at loggerheads with each other for a while. The government had tried to transfer all cases of the idol wing to the CBI citing the IG’s 'unsatisfactory performance'.