Russian warships are scouring the Atlantic for a freighter with 15 Russian crew last spotted more than two weeks ago steaming through the English Channel.
A Russian Defense Ministry statement Thursday said authorities are using all means of detection, including satellites, to locate the Maltese-registered Arctic Sea, which was due in Algeria August 4.
Moscow ordered four ships from Russia's Black Sea fleet to the Atlantic earlier this week to hunt for the freighter.
Authorities say the Arctic Sea, which was carrying lumber from Finland to the Algerian port of Bejaia, failed to arrive at its destination and did not pass through the Strait of Gibraltar.
Reports early this week says the ship was tracked as far south as the coast of Portugal before contact was lost July 28.
Swedish and Russian authorities say people dressed as police boarded the ship in the Baltic Sea just days before its disappearance. The attackers are said to have tied up the crew for 12 hours while ransacking the ship. The reports say the attackers left without taking either money or cargo.
A spokesman for the commercial maritime intelligence service Dryad told Britain's International Television Network Thursday that several aspects of the disappearance continue to puzzle experts.
Graeme Gibbon-Brooks said hijackings in the Baltic Sea and the northern Atlantic are virtually unheard of. He said modern-day piracy is normally found in areas of the world with "weak defense structures and crushing poverty."
Some information for this report was provided by AFP, AP and Reuters.