Speaking at his home during the memorial service of the deceased, Kamunyoti said three witnesses have already made their submissions in court and the other three will finalise by September.
Six police officers were charged with murder after the autopsy revealed the brothers' heads bore signs of blunt force trauma.
The six were charged on August 31, but they denied the charges and were released on a bond of Sh3 million each. Manyatta OCS and his deputy remain suspended until further directions by the court. The hearing of the case started on February 9.
Independent Medico-Legal Unit (IMLU), which has been involved in the matter, asked the State to establish a judicial inquiry to review extrajudicial killings, torture and forced disappearances.
The non-governmental organisation said it has documented 68 cases of extrajudicial killings and torture since October 30, 2020.
The death of the Kianjokoma brothers is one of the incidents reported of people killed as police officers enforced the Covid-19 regulations.
Additional 43 cases, ranging from torture to ill-treatment, were reported in 2020, while 210 cases of torture, degrading treatment and execution by police were documented in 2021.
"Out of the 210 cases, 35 were related to enforcement by Covid-19 measures, 87 deaths resulting from excessive and arbitrary use of force by police," IMLU's Executive Director Peter Kiama said.
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