A forensics report says that a former chief of staff for Guatemala's army should not stand trial for alleged involvement in the killing of 1,700 indigenous people during the nation's civil war because of his poor health.

The document by the National Institute of Forensic Science released Wednesday says 82-year-old Hector Mario Lopez Fuentes is not mentally capable of understanding others and expressing himself. The judge in the case will decide Friday whether to start a judicial process against Lopez.

Lopez was detained in 2011 on charges that he planned and ordered hundreds of massacres when he was the military leader under dictator Jose Efrain Rios Montt.

Rios Montt is facing trial on genocide charges for the killing of 1,771 Mayan Indians when he was president in 1982 and 1983.