Who killed Alexander Litvinenko?

British police investigating the murder of Alexander Litvinenko suddenly got a critical break in their case.

The polonium-210, they discovered, was easy to trace and had left a glowing radioactive trail.

If they followed Litvinenko’s movements on the day he got sick, they figured, they might be able to determine where he was murdered. And, by whom.

London Times reporter Dan McGrory followed the investigation.

Dan McGrory, London Times reporter: The police are certain in their own minds that Litvinenko was poisoned on November 1^st.

So police started where Litvinenko started when he set off from home that Wednesday.

On the morning of November 1^st, Litvinenko took a bus to central London for a series of meetings. But police found no traces of polonium on the bus... or on his bus ticket.

McGrory: We know that he went to a shop and he browsed around the shop and he bought a bottle of water and he picked up a newspaper and there was no polonium ever found in that shop. 

But just after 3 p.m., when he came to this sushi restaurant, the polonium trail suddenly lit up. There is where Litvinenko had lunch with a well-connected Italian contact.

Mario Scaramella, nuclear waste and security consultant: He was a perfectly normal.

Mario Scaramella, a consultant in nuclear waste and security, told "Dateline" he had flown in to London from Italy on business. He had secret information about Litvinenko’s friend, the murdered investigative reporter. So they slipped into the sushi restaurant for some privacy.

Scaramella: We arrived in this place and he took a box with some sushi. 

Scaramella says since it was mid afternoon and he’d already eaten, he bought just a bottle of water.

Scaramella: And we went downstairs. And we sit near a table. Alone.  No other people with us.

He handed Litvinenko e-mails from a secret Russian source. They appeared to be a kind of hit list that outlined a conspiracy.

Sure enough, one of the names in the document was that of the murdered journalist. But so was Litvinenko’s, Scaramella’s, and others too.

All those listed were apparently targeted for elimination by a shadowy Russian group of ex-KGB agents called “Dignity and Honor”.

Oleg Kalugin, ex-KGB: Dignity and Honor—

Ann Curry, Dateline correspondent: Exists?

Kalugin: —has been in existence for at least 10 years. 

Former KGB general Oleg Kalugin, says “Dignity and Honor” is a brotherhood of ex-secret agents nostalgic for hard-line Soviet ways. He says the group hunts down perceived traitors and shows no mercy.

Curry: Do they assassinate people?

Kalugin: Well, in terms of a willingness to punish traitors, well, they stated it clearly in some of the public releases they made over the years.

Curry: That they want to punish traitors?

Kalugin: Absolutely.

Curry: And—

Kalugin: That’s what—

Curry: —Alexander Litvinenko would have been considered a traitor?

Kalugin: Absolutely he was a traitor. So was I and a number of others. They have a list. 

Curry: Do you think Dignity and Honor could have killed Alexander Litvinenko?

Kalugin: They would love to kill him.

Was “Dignity and Honor” somehow involved in killing Litvinenko? Police would investigate further but for now they focused on Scaramella, who became their first suspect. After all, the radioactive poison was found in the restaurant where Scaramella, a nuclear waste consultant, met with Litvinenko.

Could it be that the Italian got hold of polonium-210, which is made in nuclear reactors, and poisoned Litvinenko in the sushi restaurant?

Perhaps, but police continued to follow the radioactive poison from Litvinenko’s day of meetings.

McGrory: And from there, the polonium trail on the day of November 1^st begins to take on quite a sinister and ominous trait.

Sometime around 4:15 p.m. that day Litvinenko came to the office of the tycoon Boris Berezovsky, who by now was also living in London.

Berezovsky told "Dateline" Litvinenko came to his office immediately after his sushi lunch to warn him. It turned out Berezovsky too was named in the hit list.

Boris Berezovsky: He call me and said “Boris, I have very important papers to give you.” And he came to my office and he copy these papers in the office and gave it to me.

But after police found traces of polonium at his office, Berezovsky became the second suspect in this murder case.

McGrory: And the police went to him, and they asked the question, “Did you have any role to play in this?”

In Russia, Berezovsky had been accused of criminal corruption. And the media there said he was ruthless enough to murder the man who saved his life and try to pin the blame on those in the Kremlin.

Were they right? Or was there something else?

Though Berezovsky had paid for Litvinenko’s house and living expenses since his escape to England, he had recently cut the funding. Was there bad blood between the two?

Whatever the truth, the mystery deepened as police investigated the next stop Litvinenko made that day, sometime around 5 p.m.

Here in the upscale Millenium Hotel Litvinenko met two well-heeled acquaintances, former KGB agent Andrei Lugovoi and his business partner. Litvinenko apparently was impressed with their success.

McGrory: He was very envious of the fact that former colleagues of his had all done extremely well financially and he had complained to a number of people endlessly that he was struggling financially.

In an exclusive interview with "Dateline," Lugovoi said he’d flown in from Moscow to watch an international soccer match. He said he was also using the trip to drum up business for his security company, which specializes in bodyguard training.

He and his business partner, who’d arrived from Germany, said they wanted Litvinenko to broker business deals with British companies.

Lugovoi, via a translator: He put me in contact with serious companies with good reputations around the world. He was the middle man and was interested in picking up a big commission…

In the hotel bar, Lugovoi and his partner apparently ordered shots of gin while Litvinenko, who never drank, sipped a cup of tea.

Nothing seemed unusual when, sometime after six, the meeting broke up in time for the Russian’s soccer game.

McGrory: So when Lugovoi and others set off to the Stadium, Litvinenko got a lift, went back to his home, and it was when he got back later in the evening that he showed the first signs of physical distress, he began to feel ill. 

But after police discovered polonium-210 in the bar where they sat with Litvinenko, Lugovoi and his business partner soon became suspects number three and four.

Was the ex-KGB agent Lugovoi perhaps linked to that shadowy group of former KGB agents called “Dignity and Honor”?

Police found themselves with a baffling case, extraordianry evidence, and an array of possible suspects including an Italian nuclear waste consultant, the tycoon Boris Berezovsky, and an ex-KGB agent and his business partner.

But as they closed in on who they thought killed Alexander Litvinenko, they discovered red flags, more compelling evidence and one critical fact about the deadly poison.

Polonium-210 is a strictly controlled substance, produced mainly in one country.

Steve Fowler, Radiation expert: Russia is believed to be the largest producer of polonium-210.

Which of their suspects might have access to the radioactive poison, police wondered?

Joyal: This was a poison constructed for this murder. This is not a mere criminal act.

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