LONDON — Vladimir Putin was today accused of running Russia like a reckless mob boss, ordering an international act of nuclear terrorism that risked thousands of lives as part of a personal vendetta.

The allegations against him and his murderous “Mafia state” were made at the start of a public inquiry into the death of a Russian dissident who was assassinated in London with radioactive poison.

Alexander Litvinenko, a former Russian spy who defected to Britain, died in November 2006 after drinking a cup of tea laced with Polonium-210 at an upmarket hotel near Buckingham Palace.

The High Court judge presiding over the inquiry said classified evidence had already established that there was a “prima facie case” linking the Russian state to the murder of Litvinenko, whose death after he swallowed the rare radioactive isotope was slow and agonizing.

Ben Emmerson, the lawyer representing Litvinenko’s widow, who has been granted access to secret intelligence files, said he would show that Putin and his associates had ordered the assassination of a man who was working with the British authorities.

“He had to be eliminated—not because he was an enemy of the Russian state itself or an enemy of the Russian people—but because he had become an enemy of the close-knit group of criminals who surround Vladimir Putin and keep his corrupt regime in power,” said Emmerson.

The Litvinenko family claims “Sasha”—as he was known to his friends—became a target for Putin when he quit the FSB, the renamed successor of the KGB, and began to speak out against its brutal and illegal operations. Head of the FSB at the time? Vladimir Putin.

Litvinenko’s outspoken attacks on Putin continued until he escaped Russia on a forged passport while he was awaiting trial. The U.S. reportedly turned down his attempt to defect, but he made it to London and succeeded in claiming asylum.

From what he saw as the relative safety of London, he renewed his attacks on Putin. He wrote a book claiming that the Russian apartment bombings that presaged the Chechen War in 1999 were an FSB false flag operation, not the work of Chechen terrorists.

He claimed Putin had links to Russian organized crime, and that the president was responsible for the murder of Anna Politkovskaya, a pioneering, dissident journalist killed shortly before Litvinenko was poisoned. The claims showed no sign of slowing down until he was taken ill at the start of November 2006. He was dead three weeks later. His body was so permeated with radioactivity that he was buried inside a lead-lined coffin at Highgate cemetery, in North London (also, as it happens, the last resting place of Karl Marx).

On his death bed, Litvinenko’s accusations continued. “As I lie here I can distinctly hear the beating of wings of the angel of death,” he said. “You may succeed in silencing one man but the howl of protest from around the world will reverberate, Mr. Putin, in your ears for the rest of your life.”

Emmerson told the public inquiry that Litvinenko’s final allegation would be proved beyond doubt. “When all the open and closed evidence is considered together Mr. Litvinenko’s dying declaration will be borne out as true—the trail of polonium traces leads not only from London to Moscow but directly to the door of Mr. Putin’s office,” he said. “Vladimir Putin should be unmasked by this inquiry as nothing more or less than a common criminal dressed up as a head of state.”

The judge heard that Litvinenko began working for Britain’s foreign intelligence agency, MI6, in 2003. In exchange for information about the inner workings of Moscow and the FSB, his handler “Martin” would arrange consultancy fees to be paid into his bank account.

Before he was killed, Litvinenko had also been working with the Spanish authorities who were planning to bring a court case that would expose the links between a criminal organization known as the Tambov-Malyshev gang and the Kremlin.

“He was killed, we say, partly as an act of political revenge for speaking out, partly as a message of lethal deterrence to others, and partly in order to prevent him from giving evidence as a witness in a criminal prosecution in Spain—a prosecution that could have exposed President Putin’s link to an organized crime syndicate,” Emmerson said.

The inquiry heard that Litvinenko had survived at least two other assassination attempts including one in 2004 when his home was firebombed by two Chechen men.

The British authorities believe that Litvinenko eventually succumbed to an assassination attempt by one man named as Dmitri Kovtun and another named as Andrei Lugovoi, a former KGB bodyguard. Litvinenko met with the men in London on two occasions that fall. It emerged today that postmortem examinations of Litvinenko’s hair revealed that he was exposed to the radioactive polonium isotope on two occasions.

Robin Tam, a lawyer acting for the inquiry, said Litvinenko had remembered feeling sick at around the time of their first meeting in mid-October. “Mr. Litvinenko recalled vomiting on one occasion about two or three weeks before being hospitalized,” Tam said. “It suggests two things—attempts to poison Mr. Litvinenko were made at both meetings and that those attempts met with some success on both occasions.”

Tam said the discovery of traces of polonium at different places across London had resulted in a public safety alert. “Many thousands of members of the public, including British residents and visitors from overseas, might have been at risk from radioactivity,” he said.

The inquiry heard that the only facility in Russia where polonium-210 is produced is Avangard, a nuclear laboratory owned by the Russian Federal Atomic Agency. “This was clearly a professional assassination which was meant to leave no trace,” said Emmerson. “This was not some ham-fisted hit by a criminal gang.”

He said polonium was used because the Russians thought it would leave no trace. The radioactivity was only discovered when police acted on a hunch and called in scientists from the Atomic Weapons Establishment. Once they knew what they were looking for, the poisonous trail would act “like the breadcrumbs left by Hansel and Gretel.”

Lugovoi and Kovtun have been invited to give evidence via satellite link at the inquiry, which is scheduled to last ten weeks. Both men deny any involvement and remain in Russia, where they have become minor celebrities.