UNITED NATIONS-- Three million Syrians will have registered as refugees outside of their country later Friday, the UN refugee agency (UNHCR) reported, with the UN high commissioner for refugees, Antonio Guterres, calling the Syrian crisis the "biggest humanitarian emergency of our era."

"The United Nations Refugee Agency (UNHCR) today announced that the number of people who have fled Syria will top 3 million today, " UN spokesman Stephane Dujarric said at a daily news briefing here.

Nearly half of all Syrians have now been forced to abandon their homes and flee for their lives. One in every eight Syrians has left the country, while 6.5 million people -- more than half of whom are children -- are displaced within the country.

"All of this comes amid reports of increasingly horrifying conditions inside Syria, with people going hungry and civilians being targeted and indiscriminately killed," Dujarric said.

Guterres said in Geneva, Switzerland, that the world is failing to meet the needs of Syrian refugees and the countries hosting them, adding that while the response to the crisis has been generous, it falls far short of what is needed.

The vast majority of the refugees remained in countries neighboring Syria, with the highest concentrations in Lebanon (1. 14 million), Jordan (608,000) and Turkey (815,000), according to UNHCR. In addition to the three million registered refugees, governments estimated that hundreds of thousands more Syrians had sought sanctuary in their countries with more than four in five refugees struggling to make a living in towns and cities outside of camps, with 38 percent living in sub-standard shelter, according to a recent survey.

Syrians are now the world's largest refugee population under UNHCR care, second only in number of refugees brought along by the decades-long Palestinian crisis. The Syria operation is now the largest in the UN agency's 64-year history.

Jens Laerke, the spokesman for the UN Office for the Coordination of Humanitarian Affairs (OCHA), said that more than 191,000 people had lost their lives since the beginning of the Syrian conflict in March 2011. The real death toll might be much higher, he said.

The advance of Islamic State (IS) militants into central Syria had taken violence against civilians to a whole new level as the group continued to commit horrific atrocities against those opposing its rule. There had also been an increase in the use of barrel bombs by government forces in Aleppo while Islamist militants had cut off the water supply to an area for displaced people, also in Aleppo, on several occasions. That kind of collective punishment was clearly a breach of some of the most basic principles in international humanitarian law.

Overall, nearly 11 million people are in need of aid in Syria and 4.7 million of them live in areas that are hard to reach. There are still some 241,000 residets under siege in various locations. Laerke said that the United Nations has now sent nine shipments to Syria from neighboring countries and more are planned over the following month.

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