The director of the Nahdha Dam project, Simgnio Bekele, who was found dead in his car in Addis Ababa on July 26, has committed suicide, Ethiopian police said on Friday.
Dozens marched after Simgnio's death in the capital and in his hometown, believing they had been killed and called for retribution.
"The investigation revealed that he used his weapon and killed himself," the head of the federal police commission in Ethiopia, Zeno Gamal, told reporters.
Simgnio was the facade of the $ 4 billion Al Nahda Dam, built on the Nile, which Ethiopia sees as the cornerstone of its quest to become Africa's largest electricity exporter.