Guatemala's highest court has ordered the annulment of the human rights trial against one of the Central American country's former dictators, sending the landmark case back to square one.

The Constitutional Court's decision Tuesday says the case of Efrain Rios Montt now goes back to a judge who asked that the proceedings start over at a point before the retired general was charged with genocide.

The 86-year-old Rios Montt is accused of responsibility for the deaths of 1,771 Mayan Indians during the military dictatorship that he headed from March 1982 to August 1983 as part of a U.S.-backed "scorched earth" campaign aimed at wiping out support for leftist guerrillas.