The NIA made the arrests on April 26, a senior government official said adding, the accused have been remanded to NIA custody and investigations are on.
The Joint Director of social welfare department, who is also the drawing and disbursing officer (DDO), Joint Director/DDO of the land resources department and UDA/cashier in the same department were arrested for allegedly extorting and collecting illegal tax in the name of NSCN(K) from various government organisations and others in Dimapur and Kohima.
The accused allegedly provided substantial amount of money to NSCN(K) by diverting government funds, officials said.
The Centre has declared NSCN(K) as a banned outfit.