Four of the world's biggest tech companies - Facebook, Microsoft, Twitter and YouTube - have teamed up to form a new coalition to make their services "hostile to terrorists and violent extremists."
The Global Internet Forum to Counter Terrorism, announced on Monday that it aims to formalise existing and future areas of collaboration among the companies.
The group said it also expects to foster co-operation with smaller tech companies, civil society groups and academics, governments and supra-national bodies such as the European Union and the United Nations on developing policies and technologies to thwart the dissemination of terrorist content.
"The spread of terrorism and violent extremism is a pressing global problem and a critical challenge for us all," the companies said in a joint statement.
"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."
Among the specific goals outlined by the companies are defining "standard transparency reporting methods" for terrorist content removals and commissioning research related to the removal of such material to help guide future policy and technical decisions.
The companies said the new forum will build on existing initiatives including the EU Internet Forum and the Shared Industry Hash Database, which tracks unique digital "fingerprints" for violent terrorist photos and videos.
All four of the companies have been criticised for not doing enough to fight terrorist activity on their internet services, and in some cases have been sued by families of people killed in terrorist attacks.
