Thousands of Argentines gathered at the National Congress on Wednesday evening in the latest of a series of demonstrations to protest a court verdict last week that acquitted five men charged in connection with the 1994 bombing of a Jewish community center here.

The protest, organized by leaders of Argentina's 300,000-member Jewish community, called for citizens of all religious groups to speak out against the culture of impunity that many say has existed in the country for too long.

"We feel that impunity has defeated justice in this case," Luis Czyzewski said at an earlier protest, held two blocks from the bombing site. Czyzewski's 21-year-old daughter, Paola, and his wife, Ana, were both inside the community center when the bomb exploded. His wife made it out alive; his daughter did not.

The July 18, 1994, attack on the headquarters of the Argentine Jewish Mutual Association killed 85 people and injured about 300. It was one of the deadliest attacks on Jews since World War II.

On Sept. 2, after a three-year trial, a three-judge panel acquitted the five men, including four provincial police officers, on charges of helping to blow up the community center, known by its Spanish acronym, AMIA. The ruling has angered family members and others close to the case, who complain about the government's inability to prosecute and convict those responsible for the bombing. The acquittal also has raised questions about how President Nestor Kirchner plans to proceed with the politically sensitive case.

Kirchner "said the AMIA bombing was Argentina's September 11th," said Sergio Widder of the Simon Wiesenthal Center in Buenos Aires. "The end of this trial shows us that the president knows very well the importance and the impact of the AMIA bombing . . . but Argentina failed in bringing those responsible to justice."

Since taking office in May 2003, Kirchner has won high public approval ratings for pushing the prosecutions of high-profile cases such as the AMIA bombing and of people involved in what came to be known as Argentina's dirty war of the 1970s and 1980s.

Last year, Kirchner compelled Argentine intelligence agents to testify for the first time about the AMIA investigation by waiving secrecy provisions. However, the agents said the investigating judge in the case, Juan Jose Galeano, had authorized that one of the defendants be paid $400,000 in return for his testimony. The report of the payment to Carlos Telleldin, who sold the car used in the bombing, ended the prosecution's hope for a conviction, according to Argentine journalists following the case.

"That was exactly the day the case collapsed. That was the big missile that sunk it," said Sergio Kiernan, who has reported extensively on the AMIA case.

As a result, Galeano was removed from the case and now faces an investigation. In a statement released after last week's acquittal, the trial judges directly criticized Galeano.

"The previous judge acted to build an incriminating case in the hopes of responding to society's logical demands, while also satisfying the shady interests of immoral politicians," the statement said.

In addition, the panel ordered an investigation into members of former president Carlos Menem's administration. Menem, now in self-imposed exile in Chile and charged with corruption, has been blamed by Jewish leaders and others for impeding the investigation while he was in office.

Argentine officials have long contended that Iranian-backed groups in the Middle East engineered the attack and used the corrupt Argentine police officers to help carry it out. Menem, who has been accused of ignoring Iran's alleged involvement, has denied allegations in the news media that he received $10 million in hush money to stall the investigation.

Last year, Argentina failed in its attempt to extradite the former Iranian ambassador to Argentina, Hadi Soleimanpour, from Britain for questioning. The request set off a diplomatic dispute among Buenos Aires, Tehran and London. Iranian officials have repeatedly denied any involvement in the AMIA attack or the 1992 bombing of the Israeli Embassy in Buenos Aires. That attack, which killed 29 people, also remains unsolved.

The Kirchner government has promised a full investigation into the irregularities and corruption scandals that plagued the three-year trial concerning what was called the "local connection." But the furor over last week's decision has raised questions about whether the probes will steer the focus away from finding those who carried out the attack.

"The reality is, 10 years after the bombing, it is really hard to investigate," said Joe Goldman, an American journalist who has written a book on the community center bombing. "Really, the only chance people might have now of a new investigation is if one of the persons involved in the bombing came out and talked. I don't think that's very likely."

Yet Czyzewski maintains hope that justice will prevail and that he will someday learn who ended his daughter's life.

"The recent verdict has left us grieving," he said. "But we have to continue fighting so we can know the truth."

A relative of a victim of the 1994 bombing of a Jewish center in Buenos Aires reacts during the protest at the National Congress. At right, a man wearing a skullcap stands in front a banner that reads "85 dead are nothing."