"The 'Mukti Bahini' was divided into two groups; the 'Niomito Bahini' – or 'regular forces' – who came from the paramilitary, military and police forces of East Pakistan, and the Gonnobahini – or 'people's forces' – who were civilians. These names were given and defined by the Government of Bangladesh. ... Civilians took control of arms depots in various cities and began resisting Pakistani forces with the acquired weapons supply."
Remember there was no "Bangladeshi military" at the time. It was the Pakistani military. The East Pakistan Rifles, for example, had maintained loyalty to Pakistan until Pakistan went too far in suppressing the revolt.
"The 'Mukti Bahini' was divided into two groups; the 'Niomito Bahini' – or 'regular forces' – who came from the paramilitary, military and police forces of East Pakistan, and the Gonnobahini – or 'people's forces' – who were civilians. These names were given and defined by the Government of Bangladesh. ... Civilians took control of arms depots in various cities and began resisting Pakistani forces with the acquired weapons supply."
Remember there was no "Bangladeshi military" at the time. It was the Pakistani military. The East Pakistan Rifles, for example, had maintained loyalty to Pakistan until Pakistan went too far in suppressing the revolt.