Officials in Marcinkiewicz's government and its predecessor have denied the allegations by Human Rights Watch and in U.S. media.
But Marcinkiewicz told Polish television today that an investigation was needed because the reports could threaten Poland's security: "I will order an investigation at all possible locations, to determine whether there is any evidence at all that such events took place on our territory. This matter must finally be closed, because it could prove dangerous for Poland."
Poland is one of America's top allies in Europe. The United States has so far declined to comment on the allegations, which have caused controversy on both sides of the Atlantic.