Jubo Dal leader NRB Mamun gave testimony as the second witness against former MP Shamim Osman and 11 other accused in a crimes-against-humanity case over the killing of 10 people in Narayanganj during the July uprising. His statement was recorded on Tuesday at International Crimes Tribunal-1. Mamun said he runs a tours and travel business and is involved in Jubo Dal politics.

Mamun said he joined the anti-quota movement from July 12, 2024. He alleged that on July 19 in Jalkuri, armed people including Shamim Osman, Ayon Osman and Azmeri Osman attacked protesters. He said he was hit by rubber bullets, while Adil and Yasin, who were beside him, were shot dead.

He also described alleged attacks near Ma Hospital on July 21 and at Chashara intersection on August 5. Mamun claimed that Swajan, a young man beside him, was injured by gunfire from Ayon Osman on August 5 and that he learned of Swajan's death the following day. He alleged that Narayanganj Victoria Hospital did not provide treatment to Swajan and demanded justice for those involved.