The detained Karachi-bound ship, laden with military hardware, ammunition and explosives, was brought to the Kolkata Port from Diamond Harbour for scrutiny on Sunday.
West Bengal DGP Bhupinder Singh said the police, navy, coastguard and customs were trying to confirm the genuineness and details of the consignment carried by the ship Aegean Glory Kingstown.
The customs authorities had, meanwhile, received a communication from the UN confirming the consignment, Singh said.
"Customs will now decide the future course of action regarding the Liberia-registered ship sailing from Chittagong in Bangladesh," he said.
The cargo ship was detained by the police at Diamond Harbour in West Bengal's South 24-Parganas district last Friday.
The captain of the vessel was de-boarded and questioned on Saturday after the papers provided by him were found not in order.
"Papers and documents furnished by the captain of the ship to police and customs were found inconsistent," Singh said.
The navy and coastguard personnel after boarding the 153-m ship on Friday found a huge quantity of explosives, rocket launchers, anti-aircraft guns and smoke bombs in two large containers.
Senior police and customs officials, who expressed surprise about the Pakistan-bound ship passing through Indian waters, visited the vessel when it was anchored at Diamond Harbour on a hovercraft.India to set up new missile base in Haldia
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