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'There will be no winner in Syria,' UN chief warns, as refugee crisis grows

Most of the people living in the towns near Syria's largest city have fled, and those without money to leave were killed, rebels say. The Syrian troops have created a no-man's land, reportedly so that rebels can't re-supply the fighters inside. NBC's Richard Engel reports.

U.N. Secretary-General Ban Ki-moon warned Friday "there will be no winner in Syria," as the world body said nearly 150,000 refugees fleeing the 17-month-old conflict had registered in neighboring countries.

In Aleppo, rebels fighting in the Salaheddine district, a southern gateway to the commercial hub, said they had been forced to fall back from frontline positions on Thursday by a fierce bombardment which had reduced buildings to rubble.

"There have been some withdrawals of Free Syrian Army fighters from Salaheddine," rebel commander Abu Ali told Reuters. Others said the main frontlines in the area, which had been held by rebels for more than a week, were now deserted.

The center of the district, near Salaheddine mosque, was abandoned when Reuters journalists visited on Thursday. The only sound was the constant echo of artillery shelling. There were no rebels, no security forces, and only a few residents darting in and out to pick up belongings -- while evading army snipers.

Stringer / Reuters

After months of protests and violent crackdowns, a look back at the violence that has overtaken the country.

All-consumed fighting
President Bashar Assad, engaged in an all-consuming fight with his mostly Sunni opponents, appointed a Sunni as his new prime minister on Thursday after his predecessor fled Monday in the highest-level defection so far in an uprising that has killed around 20,000 people.

Wael Nader al-Halqi, from the southern province of Daraa where the revolt began, replaces Riyad Hijab, who had spent only two months in the job before making a dramatic escape across the border to Jordan.

Assad's authority was shaken by the assassination last month of four of his top security officials and by rebel gains in Damascus, Aleppo and swathes of rural Syria.

But he has persevered with a crackdown on opponents seeking to end half a century of Baathist rule and topple a system dominated by members of the president's minority Alawite sect.

Rebels say minority Shiite and Alawite Muslims, the groups that have ruled Syria for decades, are being left alone in the carnage inflicted by Syrian troops. NBC's Richard Engel reports.

As the battle for Aleppo raged, Iran, Assad's closest foreign backer, called for "serious and inclusive" negotiations between the Syrian government and opposition.

Assad replaces fugitive PM, deals blow to rebels in key Aleppo district

Assad has repeatedly said he is ready for dialogue, but he has vowed to crush the armed rebels he says are terrorists. His opponents say he must step aside before any talks, arguing negotiations would be meaningless while the bloodshed persists.

Machine guns operated by motorcycle brakes? Get a glimpse at the rebels fighting against Assad's forces in Syria's mountainous Jabal al-Zawiya area.

Iran made the call after gathering diplomats from like-minded states in Tehran for talks on the conflict not attended by Western and most Middle Eastern states, which have demanded Assad end his family's 40-year rule.

'Long-term civil war'
The violence has already shown elements of a proxy war between Sunni and Shiite Islam.

"There will be no winner in Syria," Ban said in a statement read by a U.N. representative to the conference in Tehran.

PhotoBlog: Syrian fighter jet strafes farming village

"Now, we face the grim possibility of long-term civil war destroying Syria's rich tapestry of interwoven communities," it said.

Refugees pour across borders
In Geneva, Adrian Edwards, spokesman of the U.N. High Commissioner for Refugees, told a news briefing that the number of registered Syrian refugees in four neighboring countries continued to grow.

'Situation is desperate' at makeshift hospitals on Syrian-Turkish border

The total includes 50,227 recorded in Turkey, where more than 6,000 Syrians arrived this week alone, the United Nations said.

"There certainly in the past week has been a sharp increase in the numbers arriving in Turkey, and there many of the people are coming from Aleppo and surrounding villages," Edwards said.

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People resisting the army of President Bashar al-Assad in northern Syria cope with loss and prepare for fighting.

"Now if you look at other areas, I think that the situation is more of a steady and continued increase, but where fighting happens we tend to see the consequences," he said.

As of Thursday night, there were 45,869 Syrian refugees registered in Jordan, 36,841 in Lebanon and 13,587 in Iraq -- which has also seen the return of 23,228 Iraqis from Syria since July 18, according to the agency.

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"In several countries we know there to be substantial refugee numbers who have not yet registered," Edwards said.

Some Syrian refugees have also turned up in other countries including Algeria, Egypt and Morocco, and Evros, the Greek region that borders Turkey, he said, adding that the numbers were "really tiny" compared to the flows to Syria's neighbors.

Reuters contributed to this report.

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