A tech-savvy U.S. teen pleaded guilty in court on Thursday to using social media to aid the Islamic State group, a crime punishable by up to 15 years in prison.

Ali Shukri Amin, 17, a resident of Virginia, admitted in court to providing advice and encouragement to IS and its supporters.

Turkey on Thursday said it was taking measures to limit the flow of Syrian refugees onto its territory after an influx of thousands more over the last days due to fighting between Kurds and jihadists.

Under an "open-door" policy championed by President Recep Tayyip Erdogan, Turkey has taken in 1.8 million Syrian refugees since the conflict in Syria erupted in 2011.

Syrian Kurdish fighters advanced towards the Islamic State group-held town of Tal Abyad on the Turkish border on Thursday, backed by U.S.-led coalition strikes, a monitor said.

The Syrian Observatory for Human Rights said Kurdish People's Protection Units (YPG) forces backed by Arab rebel fighters "stormed the town of Suluk and took control of the eastern part of it."

Syrian rebels seized most of a military airport in regime-controlled Sweida province Thursday and shot down a warplane nearby, a spokesman told AFP.

"The Southern Front has liberated Al-Thaala military airport and is carrying out mopping-up operations against remaining forces," the alliance's spokesman, Major Essam al-Rayes, told AFP.

At least 20 members of Syria's Druze minority have been killed in an unprecedented shoot-out with Al-Qaida affiliate Al-Nusra Front in northwestern Syria, a monitor said on Thursday.

The Syrian Observatory for Human Rights said the deaths came Wednesday in the village of Qalb Lawzah in Idlib province, most of which is now controlled by an alliance including Al-Nusra.

Prime Minister Tammam Salam hailed on Thursday the role of the military institution in achieving stability and security in Lebanon, while saluting its ongoing efforts to protect the country against foreign threats.

He said: “The security plans have yielded stability in Lebanon and we succeeded in defeating strife through the military.”

Army Commander General Jean Qahwaji warned Thursday that the paralysis of the cabinet harms the country's security as ministers should continue to endorse decisions to fortify the situation in Lebanon.

Qahwaji's remarks came during a meeting with a delegation from al-Mustaqbal parliamentary bloc Wednesday.

Australian Prime Minister Tony Abbott Thursday urged Asia-Pacific nations to help fight jihadist groups as he opened a regional summit on the issue with a warning that Islamic State has global ambitions.

Abbott told the conference -- attended by ministers and representatives of 30 nations as well as well as tech giants Facebook, Twitter and Google -- that it was crucial to find methods to tackle the ideology of extremist groups that have drawn thousands of foreign fighters to Iraq and Syria.

An American man has been killed in Syria, the State Department said Wednesday, without confirming a report that he died fighting alongside Kurdish forces against the Islamic State group.

Spokesman Jeff Rathke confirmed the death of Keith Broomfield, but refused to offer further details about the circumstances or when it occurred.

Norway has agreed to take in 8,000 Syrian refugees by the end of 2017, under an agreement reached Wednesday by most of the Scandinavian country's political parties.

The country now plans to welcome 2,000 Syrians this year, that is 500 more than previously planned, followed by 3,000 each year in 2016 and 2017.