In a rare disclosure by a spy agency, Russia's secret service has revealed it had an agent inside the secret police of NATO neighbour Estonia for 15 years.
A documentary entitled "Our man in Tallinn" broadcast Sunday evening on the pro-Kremlin NTV channel showed Uno Puusepp confessing to having fed Russia secrets from within the wiretap department of Estonia's KAPO secret service between 1996 and 2011.
"You learn as time goes on to live with danger, knowing that... you could spend the next 20 years in prison," said the silver-haired former double agent, who was interviewed sitting in an armchair wearing a check shirt and tie.
Estonia quickly denounced the programme as "full of half-truths and lies" and said it would investigate. A KAPO spokesman said one person mentioned in the film was taken in for questioning but later released, without clarifying possible charges against him.
The timing of the spy's confession -- coming during heightened tensions between Russia and the West over Ukraine -- led observers to speculate Moscow was trying to drive a wedge between the US and former Soviet states in the Baltic region who have joined NATO.
Thanks to Puusepp, Russia systematically obtained reports about KAPO's relations with the CIA as well as the British, Canadian, Finnish and other Baltic states' intelligence services, the documentary claimed.
Puusepp also helped Moscow to unmask foreign agents in Russia, including Valery Ojamae, who was sentenced to seven years for treason in 2001 for spying for Britain.
The film's narrator presented Puusepp as a "modest man" who could not sit idly by after Estonia broke from the Soviet Union in 1991 and embraced what he called "Russophobia" and "fascist attitudes".
According to a former Soviet agent in Tallinn interviewed in the film, it was the Estonian who offered his services to the FSB, the successor to the Soviet-era KGB.
"Estonia's secret services worked in Russia and handed over information to the United States," a former FSB chief Nikolai Kovalyov claimed in the film.
Nikolai Yermakov, who became Puusepp's handler, boasted that having an informer inside Estonia's spy agency meant Moscow "knew everything that was being planned," including spy recruitments, and that the knowledge "allowed (Russia) to take the necessary measures".