Twitter, cut off U.S. intelligence agencies from access to a service that sifts through the entire output of its social-media postings, the latest example of tension between Silicon Valley and the federal government over terrorism and privacy.

The move, which hasn’t been publicly announced, was confirmed by a senior U.S. intelligence official and other people familiar with the matter. The service—which sends out alerts of unfolding terror attacks, political unrest and other potentially important events—isn’t directly provided by Twitter, but instead by Dataminr Inc., a private company that mines public Twitter feeds for clients.

Twitter owns about a 5% stake in Dataminr, the only company it authorizes both to access its entire real-time stream of public tweets and sell it to clients.

Dataminr executives recently told intelligence agencies that Twitter didn’t want the company to continue providing the service to them, according to a person familiar with the matter. The senior intelligence official said Twitter appeared to be worried about the “optics” of seeming too close to American intelligence services.

Twitter said it has a long-standing policy barring third parties, including Dataminr, from selling its data to a government agency for surveillance purposes. The company wouldn’t comment on how Dataminr—a close business partner—was able to provide its service to the government for two years, or why that arrangement came to an end.

Read More: Wall Street Journal

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