On trial since 25 September 2006, Nshamihigo, 48, was a Deputy Prosecutor in Cyangugu, in south-western Rwanda, in 1994 during the genocide. He has pleaded not guilty.
The presiding judge, Dennis Byron from Saint-Kitts and Nevis, who is also the president of the ICTR, said that the parties will be informed of the judgment date.
Nshamihigo is accused of being involved in massacres of ethnic Tutsis who had taken refuge in several places in Cyangugu, including churches.
The prosecuting attorney Alphonse Van of Côte d'Ivoire asked the court to hand down the maximum life sentence for the accused, saying that there should not be any mercy on him.
"This man is unforgivable. He does not have the right to any emotion or to any favour. ", stressed Van.
The attorney described Nshamihigo as "an unconditional defender of ethnic Hutus.
"He is Hutu... he cannot accept Tutsis ", claimed Van.
The defence counsels, Canadians Denis Turcotte and Henry Benoit, denounced "the incongruity" of the prosecution witnesses and asked the court for the accused's acquittal.
"The chamber has ample elements to acquit Nshamihigo", remarked Denis Turcotte, adding that several prosecution witnesses placed Nshamihigo at different places of the alleged crimes.
Counsel Benoit told the court that the prosecutor has not proven beyond any reasonable doubt of the accused's guilt.
Nshamihigo pleaded for innocence in his closing remarks.
He showed remorse and regretted "the tragedy which befell on Rwanda following the assassination of the president [Juvenal Habyarimana] and thereafter the senseless killings of each other [Hutus and Tutsis]. "
Nshamihigo was arrested in May 2001 in Arusha where he worked under a false identity as a defence investigator before the ICTR.
© Hirondelle News Agency