At least 25,300 people have been confirmed dead after the 7.8 magnitude earthquake struck southern Turkey and northwestern Syria on Monday, with multiple aftershocks.
The death toll is likely to “more than double”, according to a United Nations emergency relief co-ordinator.
Martin Griffiths, speaking to Sky News on Saturday, said he expected tens of thousands more deaths.
Mr Griffiths said: “I think it is difficult to estimate precisely as we need to get under the rubble, but I’m sure it will double or more.”
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He said that a 72-hour period after a disaster was usually the “golden period” for rescues, which has since expired, but that survivors were still being pulled out of the rubble.
Meanwhile, volunteers struggling to find survivors in the quake-hit Turkish city of Antakya said on Saturday ransacking and hygiene problems were adding to their daunting task.
One resident, searching for a colleague buried in a collapsed building, said he witnessed looting in the first days after Monday’s quake before leaving the city for a village.
“People were smashing the windows and fences of shops and cars,” said Mehmet Bok (26) now back in Antakya and searching for a work colleague in a collapsed building.
German aid organisations suspended rescue operations in the quake region on Saturday, citing security problems and reports of clashes between groups of people and gunfire.
Turkish authorities have not commented on any unrest, but president Recep Tayyip Erdogan said on Saturday the government would deal firmly with looters and other criminal behaviour, noting that a state of emergency had been declared.
“We’ve declared a state of emergency,” he said. “It means that, from now on, the people who are involved in looting or kidnapping should know that the state’s firm hand is on their backs.”
Another rescuer, Gizem from the southeastern province of Sanliurfa, said she had also seen looters in the four days she had been in Antakya.
“We cannot intervene much as most of the looters carry knives. They caught a looter today, people chased after him,” she said in the city where there was a heavy police and military presence directing traffic, helping rescuers and handing out food.
She described Antakya as a place of death and destruction when she arrived. “We could not hold back our tears,” she said.
“If people don’t die here under the rubble, they’ll die from injuries, if not they will die from infection. There is no toilet here. It is a big problem,” she said, adding that there were not enough body bags for all the dead.
“The bodies are all over the roads, with only blankets on them.”
People were wearing masks to cover the smell of death.
Others echoed concerns about hygiene, especially insufficient numbers of working lavatories.
There were long lines at temporary mobile toilets but many people said they were simply finding a hidden spot, leading to complaints about the smell.
“I think right now what’s needed most is hygiene products. We have toilet problems, I am scared that some disease will spread,” said one man, who declined to give his name and who travelled from Antalya to help in rescue operations.
He said there was little co-ordination, with everyone doing what they can to save lives and some collapsed buildings still untouched in side streets.
“We are digging for hours and hours,” he said, describing pulling alive from the rubble overnight a 56-year old woman, her face covered with dust, who had fallen into the stairwell of an apartment building.
Earlier on Saturday a second convoy of aid trucks had crossed into northwestern Syria from Turkey, as rescuers continued to pull survivors – including a newborn baby – from the rubble 100 hours after the earthquake.
Hundreds of thousands more people have been left homeless and short of food in often sub-zero winter conditions. Dozens of countries have pledged help and sent emergency teams.
The International Organization for Migration said on Friday the 14 aid trucks bound for northwest Syria were carrying desperately needed heaters, tents, blankets and other supplies. This is an area where civil war has left 90 per cent of the population – about 4 million people – relying on aid even before the quakes struck.
The lorries, heading for Idlib, followed a convoy of six UN trucks that crossed the only border crossing open on Thursday, at Bab al-Hawa. The World Food Programme said on Friday that it was fast running out of stocks in the area and called for more crossings to be opened. – Agencies