Mozambique's military and the opposition Renamo group were both guilty of serious crimes before a 2016 ceasefire, according to a Human Rights Watch report released Friday detailing killings and torture.
HRW called for justice over the violence that erupted between November 2015 and December 2016 as Mozambique appeared at risk of returning to its long and bloody civil war.
Renamo rebels had fought a 16-year war against the ruling Frelimo party until 1992, and unrest again boiled over in 2015.
"More than a year since the ceasefire was declared, the Mozambican government has not held anyone from its security forces or Renamo accountable," said HRW programme director Iain Levine.
"The government should investigate abuses by both sides and bring those responsible to justice."
The report gave evidence of torture and abduction by government soldiers, and of Renamo fighters launching deadly ambushes on public transportation and health clinics.
President Filipe Nyusi has vowed to push ahead with peace talks after holding a meeting with Afonso Dhlakama, head of Renamo, last August.
The meeting was held in the remote Gorongosa mountains where Dhlakama has been in hiding since 2015, surrounded by armed loyalists.
Renamo, which also holds seats in parliament, is seeking greater decentralisation and better integration of its supporters into the police and military.
Mozambique is still recovering from the 1976-1992 civil war during which one million people died in years of sporadic fighting between Frelimo and Renamo.
HRW said its report was based on 70 interviews with victims, police officers, soldiers, politicians and activists.
The government denied the allegations, while Renamo dismissed the report as "propaganda".
"Justice for both government and Renamo forces is crucial for the ceasefire to become an enduring peace," Levine said.Read Full Story