The Maltese-flagged cargo ship has been spotted 740 kilometres off one of the Cape Verde islands, off West Africa, more than two weeks after it disappeared, international news agencies reported yesterday.

The news agency AFP quoted a coastguard source saying the Arctic Sea was some 400 nautical miles off one of the islands but last night the Malta Maritime Authority could not officially confirm this development.

AFP said officials stopped short of saying which island: "The Cape Verde coastguard is in contact with international agencies and organisations that are continually informing it of the movement and progress of the ship."

The source, who spoke on condition of anonymity, said: "When the ship enters our jurisdiction, we will decide in consultation with our partners what action to take."

The Arctic Sea, which dropped off the radar in the English Channel on July 28, sparked intense speculation about its fate, with experts debating whether pirates, a mafia quarrel or a commercial dispute were involved.

The ship with 15 Russian crew members on board had been due to arrive in Algeria on August 4 with a cargo of sawn timber.

The ship was reportedly hijacked off the Baltic Sea when masked men claiming to be anti-drugs police boarded the ship, tied up the crew and searched the vessel. But the men were reported to have left after about 12 hours.

Earlier yesterday, an EU spokesman said the ship appeared to have been attacked twice but not in "traditional" acts of piracy, and Russian warships were scouring the Atlantic Ocean for the vessel.

EU Commission spokesman Martin Selmayr said: "Radio calls were apparently received from the ship which had supposedly been under attack twice, the first time off the Swedish coast and then off the Portuguese coast.

"From information currently available it would seem these acts, such as they have been reported, have nothing in common with 'traditional' acts of piracy or armed robbery at sea," he said, without delving into details.