Sophie Zhang, who said she felt like she had “blood on her hands” after working at Facebook, is willing to testify before Congress about her former employer, she told CNN Sunday. She said she had also passed on documentation about the company to a US law enforcement agency.

Zhang, who worked as a data scientist at the tech giant for almost three years, wrote a lengthy memo when she was fired by Facebook last year detailing how she believed the company was not doing enough to tackle hate and misinformation — particularly in smaller and developing countries. Zhang said the company told her she was fired because of performance issues…

Central to Zhang’s allegations about Facebook is that it doesn’t do enough to tackle abuse of its platform in countries outside of the United States. Roughly 90% of Facebook’s monthly active users are outside the US and Canada, according to its most recent quarterly filing.