The Obama administration has announced the formation of a task force to counter online propaganda by Islamic State and other militant groups as the US tries to crack down on the unprecedented use of the internet by jihadists.
A new group known as the Countering Violent Extremism Task Force will "integrate and harmonise" government efforts to prevent violent extremism in the US, White House national security spokesman Ned Price said on Friday.
Some of the changes appear largely bureaucratic, however, and reflect the government's ongoing struggles to address the Islamic State's presence online.
US President Barack Obama is working to reassure the public that his administration is succeeding against Islamic State in the wake of recent attacks in Paris and San Bernardino, California.
As part of the anti-jihadi effort, senior national security officials began meeting on Friday leading executives from US technology companies, including Apple chief executive Tim Cook, in California's Silicon Valley to discuss how to better thwart violent extremists' use of the internet.
The talks with tech leaders at the US Patent Office in San Jose were to focus on how to combat the use of social media by the Islamic State to "recruit, radicalise and mobilise" its followers, according to an agenda circulated among participants.
The meeting will also cover how technology can be used better to disrupt paths to violence and identify recruitment patterns, as well as create "alternative content" that can undercut the group, which controls large areas of Syria and Iraq.
A 2015 Brookings Institution report found that the militant group had operated at least 46,000 Twitter accounts during three months in 2014.
Apple's Cook will join the huddle in San Jose, according to sources familiar with the meeting. Facebook, Google, Twitter, Microsoft, Yahoo and LinkedIn are also planning to send senior executives, and other leading firms have been invited.
White House Chief of Staff Denis McDonough was to lead the meeting, also attended by Attorney General Loretta Lynch and FBI Director James Comey and other senior officials.
Law enforcement's struggles to crack encrypted electronic communications used by criminal and terrorism suspects is also on the agenda but is not expected to be a central focus, sources said.
Several social media companies have updated their terms of service within the last 18 months to take a tougher stance against content that can incite violence, but some are reluctant to appear too co-operative with the government because of privacy and commercial concerns.
Twitter, long maligned for being less co-operative than other companies such as Facebook, updated its policies last week to explicitly prohibit "hateful conduct".
The administration's new task force will involve the Department of Homeland Security and the Department of Justice and other federal and local agencies.
As well the State Department said it was revamping how it delivered anti-propaganda on sites like Twitter with the formation of a new Global Engagement Center. It will shift away from a heavily criticised campaign that included producing English counter-propaganda content and toward assisting allies in creating more targeted anti-militant communications.
Michael Lumpkin, a defence department official, will become the director of the new centre, which will focus on building anti-militant narratives, driving third-party content and "nurturing and empowering a global network of positive messengers", the department said.