Unrest in southern Turkey has disrupted rescue efforts following Monday's deadly earthquake, three rescue groups have said.
The death toll in Turkey and Syria from the quake has surpassed 28,000, and hope of finding many more survivors is fading despite some miraculous rescues, reports BBC.
German rescuers and the Austrian army paused search operations on Saturday, citing clashes between unnamed groups.
Security is expected to worsen as food supplies dwindle, one rescuer said.
And nearly 50 people have been arrested for looting, with several guns seized, local media reported.
Turkey's president said he would use emergency powers to punish anyone breaking the law.
An Austrian army spokesperson said early on Saturday that clashes between unidentified groups in the Hatay province had left dozens of personnel from the Austrian Forces Disaster Relief Unit seeking shelter in a base camp with other international organisations.
Read more: WHO chief arrives in Syria's quake-hit Aleppo: state media
"There is increasing aggression between factions in Turkey," Lieutenant Colonel Pierre Kugelweis said in a statement. "The chances of saving a life bears no reasonable relation to the safety risk."
Hours after Austria paused its rescue efforts, the country's ministry of defence said that the Turkish army had stepped in to offer protection, allowing the rescue operations to resume.
The German branch of the search and rescue group ISAR and Germany's Federal Agency for Technical Relief (TSW) also suspended operations, citing security concerns.
"There are more and more reports of clashes between different factions, shots have also been fired," said ISAR spokesperson Stefan Heine.
Steven Bayer, operations manager of Isar, said he expected security to worsen as food, water, and hope become more scarce.
"We are watching the security situation very closely as it develops," he said.
German rescue teams said they would resume work as soon as Turkish authorities deem the situation safe, Reuters news agency reported.
The Vice President of Turkey, Fuat Oktay announced on Saturday the death toll in Turkey has risen to 24,617.
While Turkey's President, Recep Tayyip Erdogan hasn't commented on the reported unrest in Hatay, he did reiterate on Saturday that the government would take action against those involved in crimes in the region.
"We've declared a state of emergency," Mr Erdogan said during a visit to the disaster zone today. "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."
State media reported on Saturday that 48 people had been arrested for looting, according to AFP. Turkish state media reported several guns were seized, along with cash, jewellery and bank cards.
A 26-year-old man searching for a work colleague in a collapsed building in Antakya told Reuters: "People were smashing the windows and fences of shops and cars."
Turkish police have also reportedly detained 12 people over collapsed buildings in the provinces of Gaziantep and Sanliurfa. They included contractors, according to the DHA news agency.
At least 6,000 buildings collapsed in Turkey, raising questions about if the large-scale tragedy could have been avoided and whether President Recep Tayyip Erdogan's government could have done more to save lives.
With elections looming, the president's future is on the line after spending 20 years in power and his pleas for national unity going unheeded.
Mr Erdogan has admitted shortcomings in the response, but he appeared to blame fate on a visit to one disaster zone: "Such things have always happened. It's part of destiny's plan."
Miraculous rescues after 100 hours under rubble
Among those rescued on Saturday were a family of five pulled from the rubble in Turkey's Gaziantep province.
Read more: Five million may be homeless in Syria after quake: UN
AP news agency reported the parents, two daughters and son were brought to safety after five days under their collapsed home, to cries of "God is great".
The same outlet reported that a seven-year-old girl was pulled from the debris in the province of Hatay after almost 132 hours under the rubble.
The BBC has also published footage of the remarkable rescue of two sisters in Antakya, southern Turkey, from Wednesday.
The quake was described as the "worst event in 100 years in this region" by the United Nations aid chief, who was in the Turkish province of Kahramanmaras on Saturday.
"I think it's the worst natural disaster that I've ever seen and it's also the most extraordinary international response," Martin Griffiths told the BBC's Lyse Doucet in Turkey.
"We have more than a hundred countries who have sent people here so there's been incredible response but there's a need for it," he added.
Mr Griffiths has called for regional politics to be put aside in the face of the disaster - and there are some signs that this is happening.
The border crossing between long-feuding Armenia and Turkey reopened on Saturday for the first time in 35 years to allow aid through.
And there are reports that the Syrian government has agreed to let UN aid into areas controlled by opposition groups, with whom they have been engaged in a bitter civil war since 2011.
The death toll in Syria from the earthquake now stands at more than 3,500, according to AFP - but new figures have not been publishes since Friday.
There has been criticism that the international effort to send aid to Syria has not been fast enough.
Ismail al Abdullah of the Syrian Civil Defence Force, or White Helmets, which operates in rebel-held areas, told the BBC's Quentin Sommerville that the organisation had stopped searching for survivors.
The international community has "blood on its hands," he said. "We needed rescue equipment that never came."
Sivanka Dhanapala, the Syria representative of the UN High Commissioner for Refugees (UNHCR), told AlJazeera that as many 5.3 million Syrians may be homeless following the quake.
"That is a huge number and comes to a population already suffering mass displacement," he said.