A second convoy of aid trucks has crossed into stricken north-western Syria from Turkey, as rescuers continued to pull survivors – including a newborn baby – from the rubble 100 hours after an earthquake that has killed more than 23,000 people. Hundreds of thousands more people have been left homeless and short of food in often sub-zero winter conditions after 7.8- and 7.6-magnitude quakes struck within hours of each other on Monday. Dozens of countries have pledged help and sent emergency teams. In Samandağ in Turkey’s southern Hatay province, a 10-day-old boy named Yagiz was retrieved from a ruined building overnight, while in Kırıkhan, German rescuers pulled 40-year-old Zeynep Kahraman alive out of the rubble more than 104 hours after she was buried and carried her to a waiting ambulance. “Now I believe in miracles,” Steven Bayer, the International Search and Rescue team leader, said at the site. “You can see the people crying and hugging each other. It’s such a huge relief that this woman under such conditions came out so fit. It’s an absolute miracle.” A 10-year-old boy was also saved overnight with his mother in the Samandağ district of Hatay after being trapped for more than 90 hours, while in Diyarbakır in the east, 32-year-old Sebahat Varlı and her son, Serhat, were pulled out alive 100 hours after the first quake. Hopes were fading, however, that many more people would be found alive. Barely 6% of earthquake victims who have not been rescued within five days survive, experts say, compared with 74% after 24 hours. The freezing conditions are likely to significantly reduce survival expectancy. In the Syrian town of Jindires, a Reuters reporter spoke to Naser al-Wakaa, sobbing as he sat on the pile of rubble and twisted metal that had been his family’s home and burying his face in the baby clothes that had belonged to one of his children. “Bilal, oh Bilal,” he said, shouting the name of one of his dead children. Rabie Jundiya, a rescue worker in Jindires, said: “The civil defence teams will not withdraw … until the last corpse is recovered from under the rubble.” In Gaziantep, Turkey, where the temperature was -3C (26.6F) on Friday morning, thousands of families spend the night in cars or makeshift tents, unable to return to damaged or destroyed homes. “I fear for anyone trapped under the rubble in this,” Melek Halıcı told Agence France-Presse, holding her two-year-old daughter in a blanket. The International Organization for Migration said on Friday the 14 aid trucks bound for north-west Syria were carrying desperately needed heaters, tents, blankets and other supplies. This is an area where civil war has left 90% 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. Turkey and Syria broke off diplomatic ties more than a decade ago, but Turkish officials have said the country was considering reopening a crossing into Syrian government-held territory, plus a second into the rebel-held north-west. Officials and medics said 20,213 people had died in Turkey and 3,553 in Syria. The confirmed total now stands at 23,766. Experts have said the toll is expected to continue climbing for some time yet since most people were asleep in their flats when the first quake struck, and whole districts in some towns have been reduced to rubble. The UN has estimated 24.4 million people have been affected in Syria and Turkey. The death toll from the quake has surpassed the more than 17,000 killed in 1999 in an earthquake in north-west Turkey, and the disaster ranks as the seventh deadliest this century, higher than Japan’s 2011 tremor and tsunami. The US has offered an $85m (£70.3m) aid package that it said would go on delivering “urgently needed aid for millions of people”, including through food, shelter and emergency health services as well as support for safe drinking water and sanitation. The World Bank has said it would give $1.78bn in aid to Turkey. Top aid officials are planning to visit affected areas, with Tedros Adhanom Ghebreyesus, the World Health Organization head, and UN humanitarian chief Martin Griffiths both planning trips. The Syrian president, Bashar al-Assad, made his first reported trip to affected areas since the quake on Friday while his Turkish counterpart toured his country’s stricken south amid continuing criticism of the state’s disaster response. Speaking in Adıyaman province, the Turkish president, Recep Tayyip Erdoğan, conceded that the Turkish authorities’ response to the quake was not moving as fast as the government wanted. He said some people were stealing from markets and attacking businesses. The disaster has cast doubt on whether Turkey’s 14 May election will go ahead as planned. The government’s response to the quake, widely criticised as slow and inadequate, is likely to prove a significant factor if and when the vote, expected to be the tightest for Erdoğan since he came to power in 2014, does go ahead. Amid opposition claims that the government’s “lack of coordination, lack of planning and incompetence” was as big a disaster as the quake itself, the president has called for solidarity and condemned what he described as “negative campaigns for political interest”. The Syrian government, which is under heavy western sanctions, has appealed for UN aid, but insisted it must be delivered through Damascus and not directly to rebel-held areas. Assad visted a hospital in Aleppo on Friday.