The testimony marks the first time that 33-year-old Zuckerberg has faced Congress.
Facebook CEO Mark Zuckerberg testified before US Congress on Tuesday, answering questions from lawmakers about issues including the company’s handling of user data.
The joint hearing of the Senate Commerce and Judiciary Committees comes amid questions over how Russia used the social network to spread divisive political messages during the 2016 US presidential election, and how data analysis firm Cambridge Analytica harvested the personal data of some 87 million Facebook users.
The testimony marked the first time that 33-year-old Zuckerberg has faced Congress.
In his opening statement, Zuckerberg acknowledged that the company faces “a number of important issues around privacy, safety, and democracy.”
“It’s clear now that we didn’t do enough to prevent these tools from being used for harm as well. That goes for fake news, foreign interference in elections, and hate speech, as well as developers and data privacy,” he said.
"We didn't take a broad enough view of our responsibility, and that was a big mistake. It was my mistake, and I'm sorry. I started Facebook, I run it, and I'm responsible for what happens here."
Key points of the testimony included Zuckerberg telling US Senators he is in a constant battle with Russian operators seeking to exploit the network, and revealing that Robert Mueller, the special counsel investigating alleged Russian meddling in the 2016 election, had interviewed Facebook staff.
Look back at some of the highlights from the session in the blog below: