A CARGO ship that vanished in the Channel was carrying arms to Iran and was being tracked by Mossad, the Israeli security service, according to sources in both Russia and Israel.

The Arctic Sea, officially carrying a cargo of timber worth £1.3m, disappeared en route from Finland to Algeria on July 24. It was recovered off west Africa on August 17 when eight alleged hijackers were arrested. The Kremlin has consistently denied that the vessel was carrying a secret cargo. It claims the ship was hijacked by criminals who demanded a £1m ransom.

The official version was challenged by sources in Tel Aviv and Moscow who claimed the ship had been loaded with S-300 missiles, Russia’s most advanced anti-aircraft weapon, while undergoing repairs in the Russian port of Kaliningrad.

Mossad, which closely monitors arms supplies to Iran, is said to have tipped off the Russian government that the shipment had been sold by former military officers linked to the underworld.

The Kremlin then ordered a naval rescue mission which involved destroyers and submarines. Any evidence that the Kremlin had let advanced weaponry fall into the hands of criminals or be sold to Iran would be highly embarrassing, so military officials believe a “cover story” was concocted.

“The official version is ridiculous and was given to allow the Kremlin to save face,” said a Russian military source. “I’ve spoken to people close to the investigation and they’ve pretty much confirmed Mossad’s involvement. It’s laughable to believe all this fuss was over a load of timber. I’m not alone in believing that it was carrying weapons to Iran.”

The alleged hijackers, four Estonians, two Russians and two Latvians, will go on trial in Moscow. According to the Kremlin’s account, they boarded the Arctic Sea in the Baltic by claiming their inflatable craft was in trouble and then took over the ship at gunpoint.

Sources in Moscow suggested Mossad may have played a part in the alleged hijacking by setting up a criminal gang, who were unlikely to have known anything about a secret cargo. “The best way for the Israelis to block the cargo from reaching Iran would have been to create a lot of noise around the ship,” said a former army officer.

“Once the news of the hijack broke, the game was up for the arms dealers. The Russians had to act. That’s why I don’t rule out Mossad being behind the hijacking. It stopped the shipment and gave the Kremlin a way out so that it can now claim it mounted a brilliant rescue mission.”

According to Israeli military sources, Israel received intelligence that weapons bound for Iran were being loaded in Kaliningrad, a port notorious for gun runners. “A decision was then taken to inform the Kremlin,” said the source.

Had the S-300 missiles been delivered, Iran would have significantly strengthened its air defences. An Israeli air force source said that in the event of an attack on Iranian nuclear installations, such missiles could increase Israeli casualties by 50%.

Since the Arctic Sea was retaken, Russia has imposed a security blackout. The hijackers, the crew and two investigative teams were flown back to Moscow in three Il-76 air freight planes. For more than a week after being freed the crew were not allowed to talk to their families. The captain and three crew are still on board the ship, which has resumed its voyage to Algeria, but they have not been able to call home.

Last week Mikhail Voitenko, an outspoken piracy expert who disputed the Kremlin’s original version of events, fled Russia, claiming he had received threats from an official angered by his statements.

Admiral Tarmo Kouts, former commander of Estonia’s armed forces and the European Union’s rapporteur on piracy, has infuriated Moscow by saying the only plausible explanation of the mystery is that the ship was transporting weapons. A spokesman for the Finnish owners denied that missiles could have been secretly loaded onto the ship.

Sources who suspect Mossad’s involvement point to a visit to Moscow by Shimon Peres, the Israeli president, the day after the Arctic Sea was rescued. Peres held four hours of private talks with Dmitry Medvedev, the Russian president. Although the Israeli foreign ministry would not be drawn on the Arctic Sea, it confirmed that the two leaders had discussed the sale of Russian weapons to countries hostile to Israel. According to Israeli officials, Peres received verbal guarantees from the Russians that they would not sell advanced weapons systems to Iran or Syria.

“Clearly the Israelis played a role in the whole Arctic Sea saga,” said a Russian military source. “Peres used the incident as a bargaining chip over the issue of arms sales to Arab states, while Israel allowed the Kremlin a way out with its claims to have successfully foiled a piracy incident.”

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