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The Ponary massacre (or Panerai massacre) was the sequence of events that took place between July 1941 and August 1944 in the town of Paneriai (Template:Lang-pl), now a suburb of Vilnius (Wilno), which became the mass murder site of approximately 100,000 victims, the vast majority of them Jews and Poles many from nearby metropolis of Vilnius. The executions were carried out by German units of SD and SS with help from local Lithuanians Special SD and Security Police Squad Ypatingasis būrys. The victims were usually brought to the edges of huge pits and shot to death with machine gun fire.
During the interwar period the town of Ponary was part of the Second Polish Republic, Wilno Voivodship (Kresy region). In September 1939 the region was taken over by the Soviets. After the annexation of Lithuania by the Soviet Union, the following year, the Soviet authorities started to build a huge oil warehouse for a nearby military airfield. The construction was never finished as in 1941 the area was occupied by Nazi Germany. The Nazis decided to take advantage of the large pits dug for the oil warehouses to dispose of bodies of unwanted locals. The massacres began in July, 1941, when Einsatzkommando 9 rounded up 5,000 Jewish men of Wilno and took them to Paneriai where they were shot. Further mass killings, often aided by Lithuanian police Ypatingasis burys, took place throughout the summer and fall. By the end of the year, more than 40,000 Jews had been killed at Paneriai.
As Soviet troops advanced in 1943, the German-led units tried to cover up the crime. A unit of eighty workers was formed from nearby Stutthof concentration camp prisoners and was forced to dig up the bodies, pile them on wood and burn them. The ashes were then mixed with sand and buried. After six months of this gruesome work, the brigade managed to escape on April 19, 1944. Eleven of them managed to survive the ordeal, and their testimony contributed to revealing the massacre. The information about it begun to spread as early as 1943, due to the activities and works of Helena Pasierbska, Jozef Mackiewicz, Kazimierz Sakowicz and others. Nonetheless the Soviet regime, which supported the resettlement of Poles from the Kresy, also found it convenient to deny that Poles were massacred in Panerai; the official line was that Panerai was a site of massacre of Soviet citizens only. It was only a decade after the fall of communism that the new government of independent Lithuania allowed a monument (a cross) to fallen Polish citizens to be built there.
The site of the massacre is commemorated by a memorial to the victims of the Holocaust, a memorial to the Polish victims and a small museum (currently closed). The executions at Paneriai, sometimes compared to the Katyn massacre by Polish press (since it happened in 'the East' and was mostly ignored by the communist government of People's Republic of Poland), are currently a matter of an investigation by the Gdańsk branch of the Polish Institute of National Remembrance.