The NIA re-registered the case under relevant sections of the Indian Penal Code on November 30, 2018.
In a statement, the investigating agency on Monday said that during the probe, three more accused Samir Kalicharan Mandal, Sabir Ali and Abdul Kadir were arrested.
A charge sheet was filed against the eight accused in a Special NIA court in Mumbai.
NIA further said that Khan was the main accused in the FICN smuggling racket as he was responsible for taking the delivery of FICN of face value of Rs 4,78,000 at Malda in West Bengal. Later, it would be circulated in different parts of India and delivered to another co-accused Anis Iqlakh Shaikh.