Watch: Accused of political bias by Ted Cruz, Mark Zuckerberg defends 'certain kinds of censorship at Facebook'

Facebook founder and CEO Mark Zuckerberg today defended certain kind of censorship to remove terrorist propaganda after a US lawmaker expressed concern over the social media giant's "pervasive pattern of bias and political censorship." Top Republican Senator Ted Cruz cited the 2016 controversy over how Facebook editors handled conservative-leaning political news in the trending topics feature.

"I think that you would probably agree that we should remove terrorist propaganda from the service. So that, I agree, I think it is clearly bad activity that we want to get down. And were generally proud of how well we do with that," Zuckerberg told the US lawmakers during a US Congressional hearing.

Zuckerberg was testifying before the US Congress amid a firestorm over the Cambridge Analytica data leak.

In March, it was found that British firm Cambridge Analytica tied to US President Donald Trump's 2016 campaign improperly collected profile data of up to 87 million Facebook users.He said he was "very committed" to ensure that Facebook was a platform for all ideas.

"That is a very important founding principle of what we do. We're proud of the discourse and the different ideas that people can share on the service, and that is something that, as long as I'm running the company, I'm going to be committed to making sure is the case," he asserted.

To a great many Americans that appears to be a pervasive pattern of political bias. Do you agree with that assessment? Cruz asked.Zuckerberg said, I understand where that concern is coming from, because Facebook in the tech industry are located in Silicon Valley, which is an extremely left-leaning place, and this is actually a concern that I have and that I try to root out in the company, is making sure that we do not have any bias in the work that we do, and I think it is a fair concern that people would at least wonder about.

Facebook, he said, do not generally ask people about their political orientation when they're joining the company."Mr. Zuckerberg, do you feel its your responsibility to assess users, whether they are good and positive connections or ones that those 15 to 20,000 people deem unacceptable or deplorable? Cruz asked.

Senator, I think that there are a number of things that we would all agree are clearly bad. Foreign interference in our elections, terrorism, self-harm, Zuckerberg said.