The US Senate yesterday questioned the leaders of social media giants Facebook CEO Mark Zuckerberg and Twitter founder Jack Dorsey regarding their activities during the US presidential election.

The Senate has questioned Twitter and Facebook leaders over the labeling of propaganda by President Trump and his supporters, especially during the presidential election.

Facebook CEO Mark Zuckerberg and Twitter founder Jack Dorsey said they had taken steps to prevent the spread of harmful and violent incidents.

Facebook and Twitter continue to add special notes to President Trump's claims that he is the winner, despite the massive defeat in the presidential election, claiming that the authenticity of his posts are controversial.

Social media leaders also rejected arguments by Democratic senators that such statements alone were not enough.

The Senate Judiciary Committee held the hearing on Tuesday.

Zuckerberg and Dorsey had promised lawmakers last month they would aggressively guard their platforms from being manipulated by foreign governments or used to incite violence around the election results.

These high-profile steps have angered President Donald Trump and his supporters.

Whether or not these measures will bring meaningful change to the platforms was a main focus at the hearing.

Zuckerberg said technological safeguards, as well as human monitors, are now catching most hate speech before it is reported to the company, but he acknowledged "there's still more progress to be made."

Central to the senators' questioning was whether or not the social media giants should be considered publishers and therefore be held responsible for the content that is posted on their platforms according to foreign media reports.

The CEOs stated that they should not be considered publishers because they do not create the content that users post on their sites.