Prosecutors have filed charges against Poland's last communist leader, General Wojciech Jaruzelski, over his imposition of martial law in 1981.
Gen Jaruzelski remains a highly controversial figure
Charges were laid by Poland's Institute of National Remembrance (IPN), a body that investigates Nazi- and communist-era crimes.
Gen Jaruzelski imposed martial law to halt the activities of the Solidarity trade union, led by Lech Walesa.
Gen Jaruzelski has said he expects to go on trial soon.
In the early 1980s, the communist authorities could not bear the threat posed by the rise in popularity of Solidarity. Within months of it being founded in 1980, the union became a national political movement with 10 million members.
The authorities responded by declaring martial law in December 1981. Solidarity leaders and thousands of others were jailed, many being held in internment camps.
The charges brought by the institute relate to crimes committed between 27 March 1981 and 31 December 1982 including "organising crimes of a military nature" and "carrying out crimes that consisted of the deprivation of freedom through internment", according to the Associated Press.
Gen Jaruzelski has sought to justify martial law as the lesser of two evils.
"This was our own sovereign decision - but one which took into account the realities of those times. At that time the Socialist system was the reality of that state - its backbone. And toppling that reality would have meant both civil war and foreign intervention."
He argued that a bloodbath would have followed intervention by Soviet troops.
The general was later cleared by the Polish parliament of responsibility for the deaths resulting from martial law.
Under Lech Walesa's leadership, Solidarity survived underground and went on to negotiate the end of communism in Poland in 1989.