A human-rights group is denouncing El Salvador for failing to investigate last July's killing of two elderly political activists.

Amnesty International says the murders of Francisco and Juana Manzanares were reminiscent of El Salvador's death squads of the 1980s. The group notes that local organizations fear a resurgence of the violence.

The two opposition party (FMLN) activists were found dead in their home on July 2, 2006.

In a press release on Sunday, Amnesty said it has not received a response to a letter it sent in March to El Salvador's attorney general asking for details about the investigation. Amnesty urged Salvadoran authorities to live up to their human-rights commitments by protecting the work of political activists.

The Manzanares' son, Francisco, died a decade ago in what investigators believe was a politically motivated killing. Amnesty says the couple's daughter, Marina, who is also a political activist, is still being threatened.