Rescue workers in Turkey pulled a teenage boy out of the rubble Friday, more than 100 hours after a 7.2-magnitude earthquake Sunday decimated much of the country's southeast.

They found the boy hours after rescuing another young man in Ercis Thursday. But hopes of finding other survivors were fading as cold weather and snow hampered rescue efforts in Ercis, the town hardest hit by the quake, and other towns and villages in the region.

Authorities raced to provide shelter for thousands of victims left homeless by the quake. Officials said Friday the death toll has risen to at least 573 and the number of those injured to at least 2,500 people. They expect the death toll to continue to climb as more bodies are pulled from the rubble.

The United Nations refugee agency said Friday it is launching an emergency airlift to the quake-stricken region. A UNHCR spokesman said the first of four daily cargo planes, each carrying about 500 tents and 10,000 blankets, will land Friday evening in the eastern city of Erzurum. From there, trucks will bring the supplies to the provincial capital of Van for distribution to quake victims. The spokesman says the shelter needs are great.

The International Federation of the Red Cross says its Turkish chapter has distributed more than 7,500 tents and 22,000 blankets, as well as stoves, food and clean water.

Many displaced residents have complained the government is not acting fast enough to distribute aid. Despite waiting in long lines for hours, some have been unable to get tents or shelter. Many people have been forced to sleep outdoors with blankets near campfires.

There have been reports of some people obtaining extra tents and selling them for profit, while Turkey's Red Crescent organization said 17 of its supply trucks were looted Wednesday.