JUDY WOODRUFF: Next tonight, Syria and the threat of an intensified crackdown on anti-government demonstrators.
And a warning to viewers: This story contains disturbing images.
The streets of Jisr Al-Shugur in northern Syria are deserted, its remaining residents braced for an imminent assault by the Syrian military. President Bashar al-Assad's government alleges 120 of its security forces were killed this week in the rebellious town, and aired amateur video on state television purporting to show its dead troops.
Now elite units, believed to be commanded by Assad's brother, appear poised to exact vengeance. This amateur video surreptitiously shot from a fleeing motorist appears to show convoys of military vehicles massed outside the town yesterday.
The BBC's Owen Bennett-Jones is on the Turkish side of the border with Syria, and says there are reports that thousands of young men remain in the town.
OWEN BENNETT-JONES, BBC News: I think the women and children basically have either gone to other locations in Syria or they have come here. And the people who remain are -- probably are the ones who want to fight you know, that are prepared to fight it out.
JUDY WOODRUFF: Only one route out is open, and townsfolk are taking it, fleeing in droves. At least 2,400 Syrians, and more by the hour, have crossed into southern Turkey, passing through lush groves and into temporary encampments.
OWEN BENNETT-JONES: Well, there's a camp. I was just there this afternoon. It has many, many tents about organized by the Red Crescent, in cooperation with the authorities. And they just tried to build an extension to that because of the numbers coming in. And I'm told they're looking for a new site because they realize that more are coming.
JUDY WOODRUFF: Some of the new refugees have shared harrowing stories in interviews posted online.
WOMAN (through translator): The forces attacked us, ruined our homes. They poisoned our water. I have 12 kids, no water. I'm hungry. I'm thirsty.
JUDY WOODRUFF: Turkish Prime Minister Erdogan said today his nation would accept all who seek safety there. But the Turks are loathe to criticize their southern neighbor directly.
OWEN BENNETT-JONES: The Turks are in an awkward position. They don't want to embarrass Syria too much, and they do have obviously an important bilateral relationship with Syria. So they are tending to play down what is happening. But, at the same time, they are letting the people in and they are looking after them.
JUDY WOODRUFF: The three-month Syrian uprising shows no signs of abating. Rather, it's been galvanized again by another gruesome video of a dead child, allegedly tortured and murdered by security forces.
Fifteen-year-old Tamer Al Sharei disappeared from the southern city of Daraa in April on the same day and in the same place as 13-year-old Hamza al-Khatib. Video of his brutalized corpse was released last week.
The growing terror and bloodshed have prompted new fears that the effects will reach beyond Syria's borders. Secretary of State Hillary Clinton spoke today in Abu Dhabi.
SECRETARY OF STATE HILLARY CLINTON: Sadly, under President Assad, it is becoming a source of instability in region. I don't think anyone looking at the situation can conclude that this is going to end well, unless there is a change in the behavior of the -- of the government.
JUDY WOODRUFF: The Syrian uprising and the regime's brutal response also tops the agenda at the United Nations. Britain and France sought support for a Security Council resolution condemning the Assad government.
British Prime Minister David Cameron outlined the stakes yesterday in a speech before the House of Commons.
DAVID CAMERON, British prime minister: And the violence being meted out to peaceful protesters and demonstrators is completely unacceptable. Of course, we must not stand silent in the face of these outrages, and we won't. And if anyone votes against that resolution or tries to veto it, that should be on their conscience.
JUDY WOODRUFF: But historic alliances with Syria led Russia, chiefly, to oppose the resolution. Given Moscow's veto power in the council, that could doom the measure before it can be brought to a vote.