NBC News report from 1/7/1972 that shows video of Pakistani soldiers executing students, professors and workers at Dhaka University on March 26, 1971
CBS News report from 2/2/1972 shows evidence of mass graves and widespread killing in Khulna. Approximately 100,000 people were killed in Khulna.
NBC News reports on 2/20/1972 on genocidal rapes of Bangladeshi women and girls during the Bangladesh Liberation War. The report interviews pregnant girls held at Pakistani army barracks and repeatedly raped. Some of the girls are as young as 13.
1971 Press Reports | Various outlets
1971 Press Reports | Various media outlets
You can find more reports here and here.