Mpiranya, a former presidential commander during the genocide in Rwanda, is charged among others with conspiracy to commit genocide.
The special hearings were conducted to preserve evidence for future use if the fugitive is to be finally arrested.
The ICTR, based in Arusha, Tanzania, has pleaded with Zimbabwe to apprehend the fugitive of the genocide that claimed close to a million lives in 1994.
Last year the tribunal trying suspects of the Rwandan genocide complained to the United Nations (UN) Security Council that it was encountering difficulties in tracking a top fugitive believed to be in Zimbabwe.
But Zimbabwe has denied harbouring Mpiranya.
Mpiranya is said to enjoy the sanctuary of top Zimbabwe army officials who appear to be paying back for the role the Rwandan of Hutu origin played in assisting the Zimbabwe Defence Forces and its allies during the war in the Democratic Republic of Congo.
Mpiranya reportedly recruited Rwandans, who fled their country after the end of the genocide, to fight on the side of the Allied forces.
After the war, Mpiranya reportedly accompanied Zimbabweans troops and was given sanctuary in the southern African country.
The Allied forces comprising Zimbabwe, Angola and Namibia fought a brutal war against Congolese rebels who were supported by Rwanda, Burundi and Uganda.
Proceedings for alleged top genocide financier, Felicien Kabuga, former Minister of Defence, Augustin Bizimana who are also still on the run, were also conducted and concluded.
During the hearings, both the prosecution and defence produced their witnesses and testimonies were recorded.
Once arrested, the Rwandan government wants the three top suspects, who lead the ICTR list of the most wanted fugitives to be transferred to Kigali.