Hundreds of students staged an angry protest outside Rio\'s military club as retired senior officers marked 48 years since the coup that ushered in two decades of military dictatorship. The demonstrators, including many relatives of victims of the 1964-1985 dictatorship that left 400 people presumed dead or missing in Brazil, on Thursday chanted \"murderers,\" \"torturers\" or \"cowards, we are waiting for the truth.\" They shouted insults at the elderly retired officers as they emerged from their luncheon meeting in central Rio and made their way to a nearby subway station, protected by a police cordon. Angela Barroso, a retired lawyer, told AFP that while she was a law student in 1968, she was arrested at her university, tortured and jailed for five months. \"You never forget torture,\" she said. Unlike other South American countries that had right-wing dictatorships and political abuses and killings during the 1960s-80s -- Argentina, Paraguay, Uruguay and Chile -- Brazil has never put the perpetrators on trial. A 1979 amnesty law, upheld by the Brazilian Supreme Court in 2010, paved the way for the return of political exiles but also protected the perpetrators of dictatorship-era crimes. Earlier this month, a Brazilian judge dismissed charges brought by four public prosecutors against a retired army colonel linked to the disappearance of five leftist militants during the dictatorship. The federal judge in Maraba in the Amazon state of Para said the charges ran counter to the 1979 amnesty law. President Dilma Rousseff, a former leftist guerrilla jailed and tortured during the 1964-1985 dictatorship, has endorsed the creation of a truth panel to probe the rights abuses during the period. The commission is tasked with probing politically-motivated abductions in the Cold War-era, rights abuses and murders over a time span exceeding the dictatorship -- 1946-1988. But it does not lift the amnesty for those who carried out the crackdown. Last year, the Inter-American Court of Human Rights dismissed Brazil\'s amnesty law as being legally invalid, saying it was incompatible with the American Convention on Human Rights.