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Hospitalized Russian spy linked to Russia-UK spy wars

Moscow(CNN) The poisoning of former Russian spy Sergei Skripal and his daughter in the United Kingdom has cast new light on a long-running intelligence feud between London and Moscow, reviving a troubled chapter in the history of British espionage.

Russia considers Skripal a traitor. On August 9, 2006, Skripal was sentenced to 13 years in prison for spying for Britain, according to Russian state media accounts of the closed hearing. Russian court officials said Skripal had received at least $100,000 for his work for MI6, Britain's foreign intelligence service, Russian state news agencies said.

Skripal's conviction was not the only setback for British intelligence that year. In January 2006, Russian state television aired a report that featured footage of British spies planting a fake rock on a Moscow street to hide electronic equipment that their sources used to exchange information.

"The spy rock was embarrassing," said Jonathan Powell, the chief of staff to former Prime Minister Tony Blair, admitting the fiasco in a 2012 BBC documentary. "Clearly they (the Russians) had known about it for some time and had been saving it up for a political purpose."

New revelations from the Russian investigation into British espionage continued. In 2007, Russian security service officer Vyacheslav Zharko confessed to working for British intelligence, the FSB said and state media reported. In a statement, the FSB identified Zharko's recruiter as Pablo Miller, described by the Russian intelligence agency as an MI6 agent working under cover as a first secretary at the British embassy in Tallinn, Estonia. The agency also identified Miller as Skripal's handler.

"During the investigation, witness Vyacheslav Zharko identified MI6 operative Pablo Miller, who was previously involved as a suspect in a criminal case against Sergei Skripal, a former Russian colonel sentenced last year to 13 years in prison for spying for Britain," the FSB said in a 2007 statement.

Fast forward more than a decade. Skripal -- who was granted refuge in the UK after a high-profile spy exchange between the United States and Russia in 2010 -- was found unconscious Sunday along with his daughter, Yulia, on a shopping-center bench in the southern English city of Salisbury. Police confirmed Wednesday that a nerve agent was used in the attack. A police officer who helped them was also exposed to the nerve agent.

Police say a total of 21 people have been treated for exposure to the agent, including the police officer and the two Russians.

Amid heightened tension between Russia and the West, the Salisbury case has drawn intense media scrutiny. That's little surprise: The Steele dossier, the 35-page document that is at the heart of the Trump-Russia investigation, was created by a former MI6 agent.

The Miller connection

What connects Salisbury to the spy wars of the mid-2000s? A man named Pablo Miller also has an address in Salisbury, according to his LinkedIn account.

A LinkedIn profile for Miller is no longer available. A summary of his profile viewed by CNN said that prior to his retirement in February 2015, he specialized in the former Soviet Union, Russia and Eastern Europe.

His diplomatic postings included Tallinn -- where, the Russians allege, he carried out espionage work. According to LinkedIn, Miller graduated from Oxford University in 1982 with a degree in Modern Languages and History, and subsequently attended the Royal Military Academy Sandhurst, the British Army's officer training academy. He was commissioned into the Royal Tank Regiment and served in Germany, Cyprus, Northern Ireland and Brunei.

CNN was not able to reach Pablo Miller of Salisbury for comment, or confirm that he is the same man the Russians have alleged to have been a former MI6 agent.

Little else is publicly available about Miller's diplomatic career. In June 2015, he received the Order of the British Empire, an honor awarded "for service to British foreign policy." While it is common for intelligence agents to work under diplomatic cover, foreign ministries rarely confirm such arrangements. A British Foreign and Commonwealth Office spokesperson said the ministry does not comment on intelligence matters.

"He enjoys a wealth of experience and expertise in the management of high-end Insider threat risks," the LinkedIn biography states. "Pablo continues to work part-time for the Foreign Office on a contract basis."

A cautionary tale to potential traitors

Russian officials say they have no information about the cause of the Skripal poisoning. But Russian media -- and the Russian embassy in London -- have indirectly expressed some glee over the incident.

The anchor of a news program on Russia's First Channel commented in a Wednesday broadcast that the Skripal case was a cautionary tale to potential traitors.

"The traitor's profession is one of the most dangerous in the world," said the anchor, Kirill Kleymenov. "According to statistics, it is much more dangerous than a drug courier. Those who chose it rarely live in peace and tranquility to a venerable old age. Alcoholism and drug addiction, stress, severe nervous breakdown and depression are the inevitable occupational illnesses of the traitor. And as a result -- heart attacks, strokes, traffic accidents, and finally suicide."

The Russian embassy in London -- known for its provocative Twitter account -- was more blunt. Posting a screengrab of a newspaper headline describing the hospitalization of the "Russian spy and his daughter," the embassy wrote: "He was actually a British spy, working for MI6."

Sandi Sidhu contributed reporting
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