By Rob Cameron
BBC News, Prague
The Czech Republic's best-known author, Milan Kundera, has spoken to the media for the first time in 25 years to deny claims he informed on a suspected Western agent in 1950.
Milan Kundera was an ardent communist in his youth
The claims, published in the leading news weekly Respekt, were made by a researcher at the country's Institute for the Study of Totalitarian Regimes.
The shelves of the newly-founded institute contain many secrets.
The institution is home to hundreds of thousands of files belonging to Czechoslovakia's communist-era secret police, the StB, as well as those of the interior and defence ministries.
Earlier this year, researcher Adam Hradilek was sifting through the police archives as part of his research into a "fairly typical" case of betrayal and Cold War intrigue in the 1950s.
"The archives offer valuable material for seeking out eyewitnesses and provide the scholar with an unprecedented tool for reviving memories," Mr Hradilek writes in Respekt.
He had no way of knowing how explosive this particular case would become.
The case concerned Miroslav Dvoracek, a young pilot who had fled Czechoslovakia shortly after the communists came to power in February 1948.
He was later recruited as a Western agent and in March 1950 he returned to Prague on an undercover mission.
Mr Dvoracek's mission, however, ended almost as soon as it began. His presence in Prague was betrayed to the police. He was arrested, tortured and sentenced to death for "desertion, espionage and high treason".
The sentence was commuted to 22 years hard labour, of which he served 14 in communist prison camps. In 1968 he emigrated to Sweden, where he still lives. According to Respekt, he refuses to talk about his arrest or imprisonment.
Earlier this year, while looking into the circumstances of Mr Dvoracek's arrest, Adam Hradilek stumbled across a police report dated 14 March 1950.
It contained the startling assertion that a student named Milan Kundera had reported to the police the presence of one Miroslav Dvoracek at a student dormitory in Prague. Mr Dvoracek had left a suitcase with a female acquaintance of his, a student at the dorms, and would return that evening.
She was questioned, and it soon transpired that Mr Dvoracek was a former pilot who had crossed the border - illegally - into Germany the previous year. Their suspicions aroused, the communist police sent armed officers to arrest the suspected spy.
The Institute for the Study of Totalitarian Regimes told the BBC there is no doubting the police report is genuine. A facsimile of the document has been published in the Czech media; it clearly shows the author's name, date and place of birth.
The Institute also said it had interviewed the female student, now an elderly woman, who offered her room to Miroslav Dvoracek on that fateful evening. She had mentioned Mr Dvoracek's re-appearance to her boyfriend - a communist student and friend of Mr Kundera's.
Milan Kundera as a young man was also an ardent communist, penning a number of poems and songs glorifying the country's socialist new order.
However he soon lost his illusions, and was expelled from the Communist Party. He later played a key role in the communist reform movement of the late 1960s, a movement that was crushed by Soviet tanks in 1968.
In 1975 Kundera, author of The Unbearable Lightness of Being, The Joke and Life is Elsewhere, emigrated to France, where he has lived ever since. He lives virtually incognito, and only visits the country of his birth in disguise. He has not given an interview in 25 years.
On Monday, however, Milan Kundera broke his vow of silence to dismiss Adam Hradilek's claims as "lies".
"I have been absolutely taken aback by something that I did not expect, something that I did not know about until now, and something that did not happen," the author said in a telephone interview with the Czech News Agency.
"I absolutely did not know that person [Miroslav Dvoracek]," said Milan Kundera. The Respekt article, he said, was "an assassination attempt".
It is almost 19 years since the fall of communism, and most Czechs have sought to bury unpleasant memories of the period.
This case, however, shows that the country's totalitarian past is never very far from the surface.