Lithuanian authorities slammed a string of incidents where anti-Semitic slogans were found near a synagogue and Nazi German flags raised to mark the 122nd birthday of Adolf Hitler.
"We strongly condemn the display of Nazi flags and slogans," Lithuania's foreign ministry said in a statement.
"They are an attack on the Lithuanian state and civil society. They incite hatred toward the Lithuanian Jewish community and should be treated as a provocation against Lithuania," it added.
Irene Degutiene, the Baltic state's speaker of parliament, said in a separate statement that she "resolutely condemns such repeated racist and chauvinist attacks" and hoped the masterminds and perpetrators would be caught and punished.
"Such incidents serve to discredit any healthy patriotism and nationalism," she said on the parliament's website.
Early Wednesday, three flags with Nazi Germany's swastika symbol were found raised on a hill close to the centre of the capital Vilnius and another one on a bridge on the city's outskirts, police said.
The other incident occurred in Lithuania's second city, Kaunas, where "Hitler was right" in Lithuanian and the German-language "Juden Raus" (Jews out) were found on a banner left near a synagogue.
Lithuania was once home to a thriving Jewish community of 220,000, with
Vilnius a hub of learning known as the "Jerusalem of the North".
But 95 percent of Lithuania's Jews perished during the country's 1941-1944
German occupation at the hands of the Nazis and Lithuanian collaborators who saw Hitler as a bulwark against the Soviet Union.
Today there are around 5,000 Jews in Lithuania, of whom around 500 live in Kaunas, according to Lithuanian-Jewish community organisations.
Nazi Germany dictator Hitler was born in 1889 and killed himself in 1945 just days before his regime's defeat in World War II. His birthday on April 20 is seen as a key commemoration by neo-Nazis.