(CNBC) The S&P 500 and Nasdaq Composite closed lower for the first time in four sessions on Thursday after the release of weak U.S. home sales data while Wall Street digested the latest news on the U.S.-China trade front.

Declines in the communications services group, led by Facebook, pushed the S&P 500 down 0.1 percent to 2,808.48. Facebook shares also weighed on the Nasdaq, which closed down 0.2 percent at 7,630.91. The Dow Jones Industrial Average, meanwhile, eked out a 7.05-point gain to close at 25,709.94.

Facebook shares slid 1.9 percent after a worldwide outage of its core app, Instagram and WhatsApp. The social media company’s stock was also under pressure after The New York Times reported federal prosecutors are conducting a criminal investigation into data deals the company made with other tech giants.

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