By Amber Henshaw
BBC News, Addis Ababa
Ethiopia is lodging an appeal to demand the death sentence for the country's former ruler Mengistu Haile Mariam and his closest aides.
Thousand's of Mengistu's opponents were killed
Mengistu and his associates were found guilty of killing thousands of people by the country's high court during the regime's 17-year rule.
State prosecutor Yosef Kiros said he wants the life sentence handed out last month to be overturned.
Mengistu is in exile in Zimbabwe, which says he will not be extradited.
The three judges who handed out the life sentences were divided over the verdict.
The presiding wanted the death penalty but the other two thought life sentences were more appropriate because of the men's health and ages.
Mr Yosef said the defendants did not deserve the court's sympathy and that some of them should get capital punishment.
A lawyer defending two of the men said he was not surprised by the prosecution's decision.
In total, 73 people were charged with genocide and crimes against humanity - 33 appeared in court, 25 including Mengistu were tried in absentia, another 14 died during the 12-year case and one man was acquitted.
Mengistu's military committee, known as the Derg, came to power in 1974 after they toppled Ethiopia's last emperor Haile Selassie.
The most brutal period of the regime was known as the Red Terror when suspected opponents and intellectuals were rounded up and killed.
Many of their bodies ended up in mass graves or were just tossed into the street for families to collect.