Shopkeepers clashed with looters and hungry families huddled under makeshift tents waiting for relief supplies on Monday after the worst-ever earthquake wiped out entire villages, buried roads in rubble and knocked out electricity and water supplies. The death toll ranged from 20,000 and 30,000 and was expected to rise.

The United Nations warned that over 2.5 million people are in need of shelter after Saturday's 7.6-magnitude quake.

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With landslides still blocking roads to many of the worst hit areas, Pakistan's army was flying food, water and medicines into the disaster zone. The US military planned to send eight helicopters from Afghanistan.

In Muzaffarabad, the capital PoK, an Associated Press reporter saw shopkeepers scuffle with people who were trying to break locks of shuttered businesses. They beat each other with sticks and threw stones, and some people were left with bleeding head wounds. No police were in the area to keep order.

Residents also reported that people had started looting deserted homes and even gas stations. Survivors complained of shortages of food and water and there appeared to be little if any official coordination of relief in the devastated city.

About 2,000 people huddled around campfires through the cold night on a soccer field on the city's university campus, where most buildings had collapsed and hundreds were feared trapped inside.

Soldiers with shovels and iron bars were trying to burrow into the concrete to find survivors.