A memorial has been unveiled to 26,000 victims of the Holocaust, which for the first time specifies that the victims shot in a forest on the edge of the capital were Latvian and German Jews.
"It is a sad and black day in the history of Latvia, one about which we wish to tell our people and our children," President Vike-Freiberga told around 400 people assembled at the six mass graves in Rumbula forest.
The victims were shot at a rate of 1,000 per hour while lying on top of those who had died before.
The Baltic state was the killing ground of some 77,000 Latvian Jews and another 30,000 to 40,000 sent by cattle truck from across Western and Central Europe as part of Nazi leader Adolf Hitler's efforts to wipe out all Jews.
Of the 26,000 Jews shot at Rumbula 25,000 were from Latvia and 1,000 from Germany.
"We remember the suffering of the innocent victims who were murdered here, we bow our heads in respect," Vike-Freiberga said.
During almost five decades of Soviet rule in Latvia, Nazi atrocities and Latvians' participation in the Holocaust were largely ignored.
Members of Latvia's small Jewish community expressed satisfaction that the memorial referred not only to Nazi German forces who directed the shootings of Nov. 30 and Dec. 8, 1941, but also to the role of "local collaborators."
"It's very impressive," said Joseph, a 93-year-old who thought the graves might contain the remains of his father and two sisters as he peered at the inscriptions.
"There were Latvian police who took part, they must say it in a clear way," Joseph said.
Critics have accused Latvia's post-Soviet authorities of emphasizing the thousands who perished in distant Soviet labor camps at the expense of acknowledging Latvians' participation in the Holocaust.
"It is uncanny that some people are adopting the Nuremberg defense used by the Nazis at their postwar trial. They too denied responsibility for their actions, saying they were 'just following orders,'" Brian Carlson, the U.S. ambassador to Latvia, told a Jewish community gathering earlier.
Of the 1,700 people who took part in the Rumbula killings between 1,000 and 1,500 were Latvian residents, Carlson said.Carlson's comments followed fierce debate among City Council members over the extent to which Latvian culpability should be acknowledged on the memorial plaque.
"Latvia has to be able to openly and honestly analyze our past - unpleasant historical facts cannot be changed or hidden," Prime Minister Einars Repse told the gathering at the Riga Jewish Museum. "These were our people who perished."
The United States has said that willingness of Latvia and Baltic neighbors Estonia and Lithuania to own up to their role in the Holocaust is a factor in the countries' admission to NATO, which alliance leaders agreed upon last week but remains subject to ratification by their legislative assemblies.
The Rumbula memorial, which was funded by donations from Germany, Israel, Latvia and the United States, lies behind a second-hand car market seven kilometers from the former Riga ghetto, from which victims were driven with whips.
It features a giant candelabrum with seven branches, the sacred Jewish menorah, surrounded by miniature obelisks bearing victims' names.
In the meantime, a series of TV advertisements featuring photographs of Nazi atrocities is currently being screened as part of efforts by the Nazi-hunting Simon Wiesenthal Center to encourage people in the Baltic states to reveal evidence against any perpetrators who went untried by the Soviet authorities and remain alive.
No one has stood trial in connection with Nazi crimes in Latvia since Soviet rule ended in 1991.
A Holocaust education program, initiated by Vike-Freiberga and partly funded by the United States, Sweden, the Netherlands and Israel, now includes visits by school teachers to Holocaust museums abroad, seminars and conferences and ongoing publication of teaching material.