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podcasts. BBC World Service coming to you from London a city usually known for being

fairly safe and secure for many a place of refuge. Today though we bring you the extraordinary story of an audacious

assassination that took place right here in the middle of London, a murder that

shocked the world and one that left radioactive poison all over the British capital.

But who killed the former Russian spy Alezander Levenenko in 2006 and why I'm Richard Watson and today I'm on the Palloneum

trail This was an example of state nuclear terrorism carried out on the streets of London against a British citizen who as a result died a long and very public death.

I've been a consultant for over 20 years.

I've never seen a case like this and I hope I never do again.

I just promised to Sasha one day people will know truth about you.

On the 1st of November 2006, Alexander Livignico, known as Sasha, met two men at the upmarket Millennium

Hotel in Central London.

All three were former Russian spies. Livignko thought he was safe and amongst friends, he'd just become a British citizen.

But 22 days later, he was dead, poisoned by radioactive polonium.

For this program we followed the evidence of the public inquiry into Leverniechh's murder

that's been sitting in London for the past six months

and which has just finished its public hearings.

And we've spoken to confidential sources close to the case.

Our story begins 15 years ago when Lipp Nieko left Russia for Britain with his wife, Marina.

I was scared from beginning to take this decision to go somewhere.

But finally I was very happy here for our family, for all of us.

...