Satellite images spot a tunnel system being dug at Imam Ali military base in eastern Syria, which is controlled by the Iranian military; Western intelligence believe the tunnels are being constructed to house their missiles.
Sources: Fox News
Sources: Fox News
Turkey threatens to "strangle" the United States-backed Syrian Border Security Force "before it's even born", while Syria vows to crush it and expel American military personnel from the country. Russia called the plans "a plot to dismember Syria".
The Syrian Observatory for Human Rights reports a large explosion near Damascus International Airport followed by a fire. The Syrian government says Israel struck the military site with several missiles. Israeli Intelligence Minister Yisrael Katz states that the strike "corresponds completely with Israel's policy".
The United States acknowledges that its warplanes may have hit a Syrian Army position near Deir ez-Zor Airport in eastern Syria, while conducting an operation against ISIL, killing more than 60 Syrian troops.
Russian President Vladimir Putin says he hopes nuclear warheads will not be needed to deal with terrorists, after Russia launched cruise missiles at Islamic State positions in Syria from one of its Kilo-class submarines in the Mediterranean.
The Syrian Observatory for Human Rights says at least 26 civilians have been killed in suspected U.S.-led coalition airstrikes near the ISIL-controlled town of Al-Hawl in Syria's northeast Al-Hasakah Governorate. A U.S. military spokesman in Iraq said the reports would be investigated.
U.S. officials say Russia has begun flying drones on surveillance missions over Syria in what would be Russia's first military air operations in the country since the recent military build-up at a Syrian airbase in Latakia.