Speaking to reporters here, IT department's Director General for Investigations Anjani Kumar said, "Koda is not fully cooperating in the investigation."
On Monday, Nov 2, Koda was interrogated on camera so that his statements are recorded on video for proof.
IT sources said Koda had provided information about investments made at different places, the network used to invest money and listed the names of people involved in the illegal transactions.
The IT department is continuing its search and seizure operations under provisions of the Income Tax Act and has summoned six people for questioning.
The six who have been asked to appear before the department on Nov 6 are Vinod Kumar Sinha, Sanjay Chaudhary, Devendra Mukhiya, Basant Bhattacharya, Manoj Punamiya and Anil Bastawde. Sinha and Chaudhary are close associates of Koda.
According to sources, documents related to investments of Koda, Sinha and Chaudhary have been seized. The sources said day and night searches may continue for the next two to three days.
"This is one of the largest raids against people who have developed network not only in different Indian states but also in many foreign countries," an IT source added.