KATYN, Russia - Laying wreaths at the spot where secret police massacred thousands of Polish army officers in 1940, Russian and Polish officials joined relatives Friday in remembering one of the Soviet Union's most brutal actions.
A memorial dedicated Friday honored more than 4,000 Polish officers shot and dumped into mass graves in April and May 1940 - a slaughter communist authorities concealed for decades.
Nazis found the graves of the Katyn victims, who were among some 15,000 Polish officers killed by Josef Stalin's secret police, in 1943. The Soviet government in Moscow blamed the killings on the Nazis, and made discussion of the massacre taboo.
In communist Poland, all information about Katyn was banned.
''The word 'Katyn' in Poland and the whole world will remain a symbol of genocide and war crimes,'' said Polish Prime Minister Jerzy Buzek, who led Poland's delegation, which included military officers.
Russia finally admitted responsibility for the massacre in 1990, handing over secret police documents to Warsaw.
''I've come here because my father is lying here. And there are thousands like me,'' said Lukrecia Hal, a retiree who was among hundreds of relatives and other ordinary Poles who traveled to Katyn in western Russia for the ceremony.
They laid 1,500 wreaths along the walls, where the Polish section is marked by a large Catholic cross. Icon lamps illuminate the names of 4,421 officers who were executed.
Poland's Roman Catholic Cardinal Josef Glemp and Bishop Slawoj Leszek Glodz, Poland's chief army chaplain, celebrated a memorial Mass. Russian Orthodox, Muslim and Jewish clerics also said prayers.
The mass graves also contain the bodies of some 500 Russian and other Soviet victims of the Nazis.
''Those who lie here, Russians and Poles - all of them are victims of totalitarian systems of the 20th century. Poland has never left them behind and will never forget them,'' said Andrzej Przewoznik, secretary-general of the Polish Union of Memory group.
The tragedy is still painfully felt in Poland. Russian officials worry that anger and resentment will color relations between the two countries for years to come.
''The shadow of the past should not haunt the present, and more importantly, the tomorrow, of bilateral relations between Russia and Poland,'' said Russian Deputy Prime Minister Viktor Khristenko.
''The memory of the Katyn tragedy, mutual grief for the dead, should not divide but unite our people,'' he said.
Mieczyslaw Geneja, who lost a brother at Katyn, told Poland's PAP agency that the Poles ''must forgive the Russians but not forget the crime.''