An Israeli source has claimed that the hijack by pirates of a boat which disappeared off the coast was a cover, and that the ship was carrying a Russian missile system to Iran.
The Arctic Sea and its 15 crew members, all Russian, disappeared in July. The ship was then believed to have been sailing to Algeria with a cargo of timber.
The ship was found in mid-August off West Africa, and Moscow claimed the ship had been hijacked by pirates, charging eight men with hijacking and piracy.
But a senior Israeli intelligence source told the BBC the hijacking was a cover-up story, or even a set-up by Mossad, to give the Russian navy time to intercept the ship.
It was claimed that while apparently missing for ten hours on Monday, Israeli Prime Minister Benjamin Netanyahu made a secret visit to Moscowto discuss the situation.
His spokesperson insisted that he had been visiting a "security installation inside Israel".
Dmitry Peskov, a spokesman for Russian Prime Minister Vladimir Putin, said he had not heard anything about a visit by Mr Netanyahu.
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