The Maltese, Finnish and Swedish maritime authorities say they knew the location of the hijacked Russian cargo ship, the Arctic Sea, during its disappearance, but decided not to reveal any information in order to minimise the risks for the crew of the freighter.

The Russian authorities say that interviews with the crew members revealed that hijackers seeking ransom money had threatened to blow up the ship. Moscow says eight pirates, from Russia, Estonia and Latvia, were arrested. The Arctic Sea, which was sailing under the Maltese flag, disappeared from the radar at the end of July. On Monday, after a three-week chase across the high seas, the Russian navy stormed the ship and arrested the pirates.

Because so little information about the missing ship was released, conspiracy theories and wild rumours have been doing the rounds. One such theory held that the hijacking was a story designed to cover the transport of nuclear material.