An Internet video has surfaced appearing to show a U.S. reporter missing in Syria, in what would be the first direct sign of him since his disappearance in August.

Two news organizations which have employed the freelance journalist Austin Tice said the 47-second YouTube video did appear to show him, blindfolded, but that it lacked enough information to draw conclusions about his current condition or whereabouts.

Russia on Tuesday urged the West not to "search for pretexts" in order to conduct direct operations in Syria while also calling on Damascus and Ankara to exercise restraint along their flashpoint border.

"In our contacts with NATO partners... we call upon them not to search for pretexts to carry out a military scenario or initiatives like humanitarian corridors and buffer zones," Deputy Foreign Minister Gennady Gatilov told the Interfax news agency.

Turkish troops fired across the Syrian border on Tuesday, killing a member of a Kurdish militia and wounding two others in the first such fatal shooting at the Turkish frontier, a watchdog reported.

"The three Kurds, members of a Kurdish militia hostile to the Damascus regime but also wary of the rebellion, were patrolling the border in (Syria's) Hasaka province when they were hit by Turkish army fire from the other side," Observatory director Rami Abdel Rahman told AFP.

Five Yemeni army officers being held by a shadowy Islamist group in Syria are students at a military academy in Aleppo and are not involved in the fighting that has engulfed the country, a Yemeni official said.

In a statement released late Monday on the ministry of defense website, the unnamed official denied the officers had "any link at all, and they did not participate in the events in Syria."

Rebel fighters stormed an army post in Douma killing six soldiers, while intense shelling by regime forces sent residents of the Damascus suburb fleeing in panic, a watchdog and activists said on Tuesday.

Other rebel-held bastions in and around Damascus were also bombarded at dawn as the government said it was close to crushing the last pockets of resistance in the capital.

Jordanian riot police used tear gas to disperse Syrian refugees at a camp in the north of the country who set fire to tents and destroyed property in protest at their living conditions, a charity said Tuesday.

"Some 500 refugees demonstrated against their living conditions in the Zaatari camp," said Zayed Hammad, president of the charitable Muslim association Kitab wal Sunna, which provides aid for tens of thousands of refugees.

The son of Hizbullah leader Sayyed Hassan Nasrallah was the target of the abduction of the 11 Lebanese pilgrims in Syria in May, reported Ad Diyar daily on Tuesday.

He was thought to be on the bus carrying the Lebanese back from a pilgrimage in Iran, Syrian opposition sources told the daily.

Iran on Monday added its voice to warnings against Syria ever using chemical weapons in its increasingly large-scale war with anti-government insurgents.

Foreign Minister Ali Akbar Salehi said in New York that Iran could not support any country -- including ally Syria -- that used such weapons, calling this "a situation that will end everything."

Syria's foreign minister accused the United States and its allies Monday of supporting terrorism in Syria but said his government remains open to a political settlement of its civil war.

Speaking to the U.N. General Assembly in New York, Foreign Minister Walid Muallem said France, Qatar, Saudi Arabia, Turkey and the United States "clearly induce and support terrorism in Syria with money, weapons and foreign fighters."

U.N. chief Ban Ki-moon called Monday on the Syrian government to show "compassion" to its people in the midst of an increasingly vicious civil war against armed rebels.

Ban said after a meeting with the Syrian foreign minister at U.N. headquarters in New York that it was time for Damascus to lower the scale of its offensive against the insurgency.