According to media reports all the 24 crew members of the Estonian ship are from Pakistan.
Coast Guard and CID officials are considering all angles of the detained ship, especially with the revelation that the ammonium nitrate which was meant for Indian Explosives Limited, a private company, have been manufactured in the name for fertilizers.
It has been said that authorities came to know about the chemicals when the ship was unloading its entire cargo.
The ship was anchored at Haldia Dock Complex (HDC) since December 4.
Ammonium nitrate is widely used to prepare explosives.