Facebook, Microsoft, Twitter and YouTube announced Monday the launch of an anti-terror partnership aimed at thwarting the spread of extremist content online.
The "Global Internet Forum to Counter Terrorism" intends to share engineering, research and knowledge to help "continue to make our hosted consumer services hostile to terrorists and violent extremists," the companies said.
Each of the technology giants has been working individually to prevent its platforms or services from being used to promote or spread extremist views.
"The spread of terrorism and violent extremism is a pressing global problem and a critical challenge for us all," said a joint statement posted on Twitter's policy blog.
"We believe that by working together, sharing the best technological and operational elements of our individual efforts, we can have a greater impact on the threat of terrorist content online."
The new forum built on discussions in Europe and conclusions of recent G7 and European Council, according to the companies.
The forum planned to work with smaller tech firms as well as civil groups, academics and governmental bodies.
"The scope of our work will evolve over time as we will need to be responsive to the ever-evolving terrorist and extremist tactics," the founding companies said.
US social media titan Facebook last week launched a campaign in Britain to counter the spread of online extremism after warnings from Prime Minister Theresa May that followed four attacks in three months.
Facebook said it would seek to educate charities and other organizations on how to fight hate speech, in the wake of the terror attacks in Britain as well as in Belgium and France.
The Online Civil Courage Initiative (OCCI) will act as a forum for charities and other nonprofit organizations to share their experiences of extremism and develop "best practices" to tackle the issue, both on and offline.
There are already OCCI schemes in France and Germany.
Earlier this year, Group of Seven (G7) leaders had urged companies like Facebook and Google to do more to curb extremist content online.
Facebook this month launched a series of counterterrorism measures in the wake of attacks in Manchester and London.
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