US mainstream news outlets like CBS News with actual reporters on the ground at the time: https://www.cbsnews.com/news/there-was-no-tiananmen-square-massacre/
Classified US communications with assets on the ground: https://wikileaks.org/plusd/cables/89BEIJING18828_a.html
Image Analysis
I wish the title wasn’t so clickbaity, since it sounds like they are trying to deny that there was violence at all, which would be out of touch with reality.