Michael Chakma, a leader of the United Peoples Democratic Front (UPDF), has filed a written complaint against former prime minister Sheikh Hasina and eight other individuals.
The complaint was submitted on Monday at the office of the chief prosecutor of the International Crimes Tribunal.
Prosecutor Abdullah Al Noman accepted the complaint, with Michael Chakma accompanied by former Jahangirnagar University teacher and human rights activist Rehnuma Ahmed.
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Prosecutor Noman informed that the remaining eight individuals are members of law enforcement agencies. However, he did not disclose their names.
Earlier, on December 18, Michael Chakma appeared before the tribunal and submitted an oral complaint to the prosecution.
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After filing the complaint, he told reporters, "I believe I am a victim of retaliation for my past actions, and I hold Sheikh Hasina, as the main accused, responsible for my disappearance. We have also filed complaints against those who were involved with her and those who assisted in the matter."
Michael Chakma was allegedly abducted on April 9, 2019, while returning to Dhaka after completing organisational work in the Kanchpur area of Narayanganj.