Lech Walesa collaborated with communist-era security police, Poland’s Institute of National Remembrance (IPN) claimed on February 18.

According to documents obtained by IPN from the widow of the late General Czeslaw Kiszczak, a communist-era prime minister, the former president of Poland - credited with leading the fight against communism in 1980s - signed a collaboration agreement with the state security police (SB) and took money for his services.

Walesa’s cooperation ran from 1970-1976, according to the documents. Walesa has denied the revelations, calling them a “forgery”.

“The documents contain an envelope in which there is a declaration to collaborate with the security services signed by Lech Walesa, codename ‘Bolek’,” Lukasz Kaminski, who heads the IPN, told journalists. “The documents include hand-written receipts for receiving money, signed by Bolek,” he added.

Walesa's story from before the time he became a national hero has long been the subject of speculation inside Poland. Acting as the head of the trade union-turned-opposition movement Solidarity, he organised strikes at the Gdansk shipyards and then moved onto wider opposition activities. In 1989 Walesa sat down with the communist party apparatchiks to negotiate a transition to market democracy. His career peaked in 1990 when he was elected president.

However, gossip of Walesa’s collaboration with the regime has been long-standing, with the former president not making the picture any clearer. The Nobel Peace Prize laureate would hint he had signed some documents with SB, but always denied taking money. He was also unclear on what – if any – information he gave to the security police.

The founders of the current ruling party Law and Justice (PiS) Jaroslaw Kaczynski and his late brother and former president Lech worked for Walesa in early 1990s, but have since been staunch critics of the Polish icon and the transition from communism he orchestrated. The nationalist and populist PiS claims Poland has failed to cleanse itself of the power and influence of former communist party officials and members of security services.