The whereabouts of a cargo ship, which reportedly sailed through the English Channel after it had been boarded by pirates, remained unclear today.
The Arctic Sea, which disappeared with a 15-strong Russian crew on board more than two weeks ago, was spotted about 520 miles off the Cape Verde islands yesterday, according to French officials.
But today Russian news agency Itar-Tass reported that it was still unconfirmed whether the sighted ship was the Arctic Sea.
The 4,000-tonne vessel was meant to arrive in Bejaia in northern Algeria with its cargo of about £1 million worth of sawn timber on August 4. It is unknown what happened following its last official recorded positioning off northern France on July 30.
Numerous theories have been put forward to explain the vessel's disappearance, ranging from it being boarded by pirates to a commercial dispute.
Yesterday Itar-Tass and Financial Times Deutschland reported the ship near the Cape Verde islands, while French officials also said they had located the ship in the area.
EU Commission spokesman Dennis Abbott said it was being kept informed of developments by the member states involved.
He added: "We can't say any more than that because we don't want to hinder law enforcement activities."
Russia's ambassador in Cape Verde, Alexander Karpushin, told the Vesti news channel: "I met with the country's authorities, in particular with the chief of the general staff of Cape Verde's armed forces, who did not confirm the information that the ship had been detected."
He added that the country's ports had been instructed to contact the authorities if the ship appeared and asked for refuelling, food or water.
Russian president Dmitry Medvedev has ordered all Russian navy ships in the Atlantic to search for the missing vessel.
The ship's last known radio contact was with British Coastguards when it made routine contact with Dover Coastguard as it was about to enter the Strait of Dover from the North Sea at 1.52pm on July 28.
Days later Interpol informed the British Coastguard that the ship had been hijacked days before in the Baltic Sea.
According to reports, it was boarded by up to 10 armed men purporting to be anti-drugs police on July 24.
Some 12 hours later, the intruders apparently left the ship on a high-speed inflatable boat and allowed the vessel to continue on its passage but with its communications equipment damaged.
By the time Interpol alerted Dover Coastguard about the apparent hijacking, the Arctic Sea had already passed through the English Channel, UK Coastguards said.
It was last recorded on the AISLive ship tracking system off the coast of Brest, northern France, just before 1.30am on July 30.
Mr Abbott confirmed that radio calls were apparently received from the ship to suggest it had been attacked a second time, this time off the coast of Portugal.
He added: "It would seem that these activities, such as they have been reported, have nothing in common with traditional piracy."
Nato said it was monitoring the situation but was not directly involved in the search.
The Arctic Sea's tracking system was reported to be broadcasting signals from the Bay of Biscay off France today.
The Russian maritime website, Sovfrakht, said the signal appeared on a tracking service at about 8.30am but added that it was not known if the AISLive ship tracking system equipment was still actually on the ship.