If you are talking about Sharmila Bose she just took HRC report and extrapolated the number from it. She never visited Bangladesh or talked with eye witness and victims, neither did HRC commission which constructed it's report based on log book entries of PA officers.
It doesn't matter to me actually but I happened to go through these reports in detail.
*Expecting an emotional outburst of name calling with keywords malaun, hindu, hanuman etc*
So, she made claims by egging on HRC's report, right? Then what is this?
The case studies are therefore representative of the conflict, though not comprehensive. They were selected after discussion with several Bangladeshis with a keen interest in the war, almost all strongly pro-liberation, complemented by instances suggested by researching published material from all sides. They include mob violence in early March in Khulna and Chittagong, military action on March 25-26 in Dhaka University student halls and faculty residences, army attack on Shankharipara in old Dhaka on March 26, mutiny in Mymensingh, Bengali-Bihari violence in Khulna at different times, such as Bengali attacks against Biharis in March, Bihari attacks on Bengalis subsequently and Bengali revenge after independence, Bengali-non-Bengali violence in Chittagong and Bogra areas, rebel resistance in Tangail, mass killings by the army in Rajshahi and Mymensingh, army killing of Hindu refugees in Khulna, killing of intellectuals in Dhaka in December and revenge killings by the winning side after the end of the war. The compilation is ongoing.
The paper uses data collected during 2003-05 in Pakistan and Bangladesh from site visits, interviews with survivors, eye-witnesses and participants, and related material such as images and published and unpublished eyewitness accounts and memoirs (in English and Bengali).
The approach in the project, and in this paper, is reconciliation. This refers partly to reconciliation among people. In the absence of any institutional truth and reconciliation effort, participants in the 1971 conflict remain bitterly divided, in denial to a significant degree, and without closure in numerous instances. However, reconciliation also refers to the reconciliation of fact with fiction, using a non-partisan, evidence-based approach towards a conflict whose accounts are still driven by bitter emotional partisanship. They provide the basis for an analysis that challenges both the silence and the unsubstantiated rhetoric that have obscured the study of the conflict of 1971 to date.
The paper is organised in the following manner. Section III elaborates on the chronology and typology of violence in the conflict of 1971 with illustrative examples from the case studies. Section IV discusses some of the preliminary findings on the patterns that emerge. As the project is ongoing, the illustrative examples are only taken from completed parts of the case studies, and the findings must necessarily be termed preliminary until the work is completed.
Anatomy of Violence: Analysis of Civil War in East Pakistan in 1971 by Sarmila Bose « Pakistanthinktank313's Blog