A Ukrainian man selling a poison thought to be linked to at least 130 UK deaths has been identified by the BBC.
Leonid Zakutenko advertised his services on a website promoting suicide and he told an undercover reporter he sent five parcels a week to the UK.
He has been supplying the same substance as Canadian Kenneth Law, who was arrested last year and is now facing 14 murder charges.
Mr Zakutenko denied the claims when challenged by the BBC.
He was tracked down to his home in Kyiv and denied that he sold the deadly chemical, which the BBC is choosing not to name.
However, our investigation found that he has been supplying the substance for years.
The chemical can legally be sold in the UK, but only to companies using it for a legitimate purpose.
Suppliers must not sell to customers unless they have carried out basic checks on what the substance is to be used for.
It can prove fatal if ingested in even small doses.
'Contemptible'
Zakutenko was described as a "contemptible and evil human being" by the family of twin sisters Linda and Sarah, who died in London last year after the Ukranian supplied them with poison.
Linda was given "easy access to a 'death kit' for a few pounds" after finding out about the seller on a well-known suicide forum, according to sister Helen Kite.
She described her sisters, 54, as "intelligent, caring and articulate".
