The Algerian authorities are accused of making over 7,000 people "disappear" during the 1990s in a new report by the lobby group Human Rights Watch.
The disappearances occurred during the armed struggle between the government and Islamist groups.
Human Rights Watch said the government should investigate the disappearances and hold the perpetrators responsible.
The effects of Algeria's civil war are now being felt abroad too
This new report on the gross violation of human rights in Algeria is timed to coincide with an historic visit to Algiers this weekend by French President Jacques Chirac.
The visit will be the first by a French president since Algeria's long war of independence from France, and the Algerian Government is expected to try to use it to demonstrate that the country has turned a page on its violent past.
'Decade of bloodshed'
But Human Rights Watch said the families of the 7,000 "disappeared" had a right to know what happened to their loved ones, and urged President Chirac to press for an independent commission capable of resolving the fate of the victims.
The war shows no sign of ending
Human Rights Watch also condemned armed Islamist groups for conducting massive "disappearances", and said neither they nor members of the state security services found guilty of crimes should benefit from an amnesty being proposed by the Algerian president.
A decade of bloodshed began in Algeria in 1992 when the government refused to hand power to relatively moderate Islamic party which had won elections.
The move radicalised all sides and the war which followed is estimated to have cost 100,000 lives.