Brazil's President Dilma Rousseff has signed a law establishing a truth commission to deal with human rights abuses during the country's two-decade military dictatorship.

Ms. Rousseff signed the measure Friday, along with a law granting public access to documents and records from the dictatorship era, 1964 to 1985.

Hundreds of people are believed to have been killed or disappeared during that time.

The United Nations High Commissioner for Human Rights, Navi Pillay, on Friday praised the move as "an essential and welcome first step" toward healing the country's wounds. She said bringing testimonies to light about abuses during that time will lay the groundwork for accountability for those responsible.

Unlike its South American neighbors Argentina, Chile, and Uruguay, which also suffered under years of dictatorship, Brazil has not put on trial any individuals accused of human rights abuses.  

Some information for this report was provided by AP and AFP.