Rescuers struggle to find earthquake survivors in Turkey and Syria, as more than 20,000 confirmed dead

Rescue workers made a final push Thursday to find survivors of the earthquake in Turkey and Syria that rendered many communities unrecognizable to their inhabitants and killed more than 20,000.

It was not clear how many people were still unaccounted for in both countries.

Monday's earthquake affected an area that is home to 13.5 million people in Turkey and an unknown number in Syria. Even with an army of people taking part in the rescue effort, crews had to pick and choose where to help.

The scene from the air showed the scope of devastation, with entire neighbourhoods of high-rises reduced to twisted metal, pulverized concrete and exposed wires.

Even though experts say people could survive for a week or more, the chances of finding survivors in the freezing temperatures were dimming.

As emergency crews and panicked relatives dug through the rubble — and occasionally found people alive — the focus began to shift to demolishing dangerously unstable structures.

The DHA news agency broadcast the rescue of a 10-year-old in Antakya. The agency said medics had to amputate an arm to free her.

A 17-year-old girl emerged alive in Adiyaman, and a 20-year-old was found in Kahramanmaras by rescuers who shouted "God is great."

In Nurdagi, a city of around 40,000 nestled between snowy mountains some 56 kilometres from the quake's epicentre, vast swaths of the city were levelled, with scarcely a building unaffected. Even those that did not collapse were heavily damaged, making them unsafe.

Throngs of onlookers, mostly family members of people trapped inside, watched as heavy machines ripped at one building that had collapsed, its floors pancaked together with little more than a few inches in between.

Mehmet Yilmaz, 67, watched from a distance as bulldozers and other demolition equipment began to bring down what remained of the building where six of his family members had been trapped, including four children.

He estimated that about 80 people were still beneath the rubble and doubted that anyone would be found alive.

"There's no hope. We can't give up our hope in God, but they entered the building with listening devices and dogs, and there was nothing," Yilmaz said.

Mehmet Nasir Dusan, 67, sat watching as the remnants of the nine-storey building were brought down in billowing clouds of dust. He said he held no hope of reuniting with his five family members trapped under the debris.