Cardinal Miroslav Vlk, archbishop of Prague, has asked authorities to investigate possible collaboration between priests and the communist-era secret service, Prague Radio said Thursday.

The cardinal said the state police was known for using tough methods to force priests to cooperate during the communist regime, from the 1940s to the fall of communism in 1989.

Vlk has taken the measures in an attempt to avoid any embarrassing situations, such as those which occurred recently in Poland.

Last month Archbishop Stanislaw Wielgus resigned from his appointment as archbishop of Warsaw after it was revealed that he had collaborated with communist authorities more than 30 years ago.

Cardinal Vlk proposed that a commission be established to conduct the investigation, dubbed Open Past. He reportedly spoke with Interior Minister Ivan Langer about the plan.

The commission should be comprised of experts from the ministry archives as well as Church researchers.