One million Syrians are facing food shortages because of their country's bloody conflict, the United Nations warned Tuesday, as angry refugees rioted in a camp in Jordan.

As fighting raged on in the 22-month-long conflict, NATO meanwhile started deploying a German Patriot missile unit off to Turkey to help the alliance member defend itself against cross-border fire.

U.S. and Dutch Patriot missile defense units are also en route to southern Turkey, where shells from Syria have hit civilian areas, leading Turkey to return cross-border fire in recent months.

Relations between Ankara and Damascus have deteriorated sharply since the Syrian regime of President Bashar al-Assad started cracking down on its opponents in March 2011.

The conflict has since turned into a civil war that has claimed more than 60,000 lives, according to UN estimates, devastated vast areas and created hundreds of thousands of refugees.

In Geneva, the UN World Food Program (WFP) said it was unable to expand food aid from 1.5 million people to the 2.5 million now in need, citing a lack of partners and tough logistics.

"The Red Crescent is overstretched and has no capacity to expand further," WFP spokeswoman Elizabeth Byrs told DPA.

Byrs said fighting had forced the UN agency to pull its staff out of its offices in the central province of Homs, the northern province of Aleppo and the coastal city of Tartus.

Last month, the UN appealed for an extra 1.5 billion dollars to help Syrians fleeing the conflict, warning that the number of refugees in neighboring countries could double.

In Jordan, riots erupted Tuesday in the Zaatari Syrian refugee camp which was pounded by heavy rains for a second day, damaging 500 tents and submerging much of the site under one meter of mud.

A six-year-old refugee, Lamia Hassan al-Ahmed, had died due to bad weather and harsh conditions in Zaatari camp, according to the opposition Syrian Revolution General Commission.

"We have no heating, we have no blankets, many of us don't even have shoes," camp resident Abu Yousef al-Darawi, 40, told DPA. "We were better off living under the rockets of al-Assad than dying in a Jordanian winter."

Some 200 refugees, throwing stones and wielding makeshift clubs, attacked aid workers who were handing out bread, said the state-run Jordan Hashemite Charity Organization which co-administers the camp.

Seven aid workers were wounded, several refugees arrested, and anti-riot forces fired tear gas to disperse the angry crowd, while aid workers were evacuated, said a security source.

From Europe, meanwhile, 50 German and Dutch Patriot unit advance troops flew to Turkey as the German military loaded 130 containers and 300 vehicles onto a Danish ship at Luebeck-Travemuende port.

The cargo was headed for the Turkish port of Iskenderun, where it is set to arrive on January 21.

The Patriot missiles themselves are being shipped from another location as part of the 25-million-euro mission.

The Patriots have a range of 68 kilometers and are meant to intercept any incoming Syrian missiles. They will be based at Kahramanmaras, 100 kilometres from the border.

Germany is deploying about 350 troops with the Patriots on a mission that NATO and Berlin stress is a purely defensive operation, meant to support alliance member Turkey.

"The mission is a clear sign of solidarity within NATO," said German unit commander Lieutenant General Rainer Glatz. "We enjoyed NATO solidarity during the Cold War and now we extend it to Turkey."

Meanwhile, new images emerged from Syria's brutal conflict. The Britain-based opposition group the Syrian Observatory for Human Rights documented Tuesday executions in Syria that it said had been carried out by the rival sides in the conflict.

"Reports coming from Syrian refugees escaping the village of Al-Mastuma in the northern province of Idlib said troops have stormed the village and executed around 15 men in the village," said Rami Abdel-Rahman, head of the Observatory.

Members of the Islamist group the Al-Nusra Front had executed three soldiers captured Saturday in the eastern province of Deir al-Zour, the Observatory said.

A video posted online showed three men with someone calling their names out and confirming that they belong to the Syrian religious minority the Alawites, to whom al-Assad belongs.

The video then showed the three men's dead bodies in a hole. Rebels said one of the men was alleged to have raped a young woman.
News coming from Syria cannot be verified independently as journalists are banned by the government from entering restive areas.

Meanwhile, General Adnan Silo - who was responsible for chemical weapons in the Syrian army before defecting some six months ago - charged that troops used deadly sarin nerve gas two weeks ago in the al-Bayada and Deir Balba areas of central Homs province.

"We have received confirmation that sarin gas was used in both areas and people have suffered breathing problems, palpitations and nausea," Silo told Dubai-based Al Arabiya television from Istanbul.

Silo referred to New York Times reports of satellite pictures that "showed troops appearing to be mixing chemicals at two storage sites, probably the deadly nerve gas sarin, and filling dozens of 500-pounds bombs that could be loaded on airplanes."