The head of a Sudanese chemical firm has told the BBC a shipment of explosives impounded by the Greek authorities was destined for his company.
The Baltic Sky had been on a long odyssey around the Mediterranean
Issam Bakri Khalifa, of the Integrated Chemicals and Development Company, said the consignment was intended for peaceful purposes and he has demanded it back.
The ship - the Baltic Sky - was carrying 680 tons of explosives when it was stormed by special forces off Greece's western coast on Sunday.
Greek officials said documents on board linked the ship with Integrated Chemicals and Development but initial inquiries indicated the company did not exist.
The BBC's Panos Polyzoidis in Greece says the shipment of explosives is so large that it may have been intended for a government rather than an organisation.
Greek Shipping Minister George Anomeritis said the ship's manifest showed that cargo was officially bound for a company with "a post office box in Khartoum that did not exist".
It should have reported that it was sailing with an atomic bomb cargo
Greek shipping minister
Documents from the ship described the cargo as ANFO, a commercially-manufactured ammonia nitrate-based explosive usually used in mining.
Mr Anomeritis described the ship's cargo as akin to "an atomic bomb".
The crew of seven - five Ukrainians and two Azeris - have been charged with possession and transport of explosives - an offence which carries a maximum sentence of 20 years.
They have also been charged with failing to notify Greek authorities 24 hours in advance that they were transporting explosives into Greek waters.
The ship's location when it was stopped suggested it was not heading towards Khartoum.
It had apparently been sailing around the Mediterranean for six weeks before being impounded.
It had loaded 450 pallets of TNT and 8,000 detonators in Gabes, Tunisia on 12 May, Mr Anomeritis said.
The vessel was later seen near Istanbul on 22 May and in the Aegean Sea on 2 June.
It was boarded in the Ionian Sea following a tip-off and then forced into the tiny Greek port of Platiyali, 235 kilometres (145 miles) north-west of Athens.
The discovery of the cargo comes amid heightened terror alerts in East Africa and elsewhere.
Anti-terrorist forces and army bomb experts have begun examining the cargo.