‘Catastrophic’ earthquake in Turkey and Syria kills at least 4,300 people

International rescue missions were rushing to Turkey and Syria on Monday after one of the most powerful earthquakes to hit the region in at least a century left more than 4,300 people dead, thousands injured and an unknown number trapped in the rubble.

The early-morning quake and dozens of aftershocks wiped out entire apartment blocks in Turkey and heaped more destruction on Syrian communities already devastated by over a decade of war.

Pledges of emergency assistance to both countries have poured in from across the globe, with calls for Damascus to allow aid into north-west Syria, the last rebel-held enclave and one of the areas worst hit by the shaking.

The magnitude-7.8 quake, which hit in the darkness of a winter morning, was followed by a second, 7.5 quake in the middle of the day on Monday, as rescuers in both countries were still attempting to search for survivors.

By the early evening, the death toll in Turkey stood at 2,921, the the country’s emergency services said, and more than 14,483 people were recorded as injured. Yunus Sezer, who heads Turkey’s disaster relief agency AFAD, said nearly 15,000 search and rescue personnel had been deployed to the region.

At least 1,444 people were killed in Syria, according to figures from the Damascus government and rescue workers in the north-western region, which is controlled by rebel groups.

The toll of 3,823 was expected to rise as rescue workers and residents searched frantically for survivors under the rubble of crushed buildings in cities on both sides of the border.

The quake struck at 4.17am local time at a depth of about 11 miles (18km) near the Turkish city of Gaziantep, which is home to about 2 million people, the US Geological Survey said.

“Can anyone hear me?” rescuers shouted as they searched in the province of Kahramanmaras, the epicentre. In some places around southeast Turkey, survivors could be heard screaming from beneath collapsed buildings, the Associated Press reported.

Television images from Turkey showed shocked people standing in the snow in their pyjamas, watching rescuers dig through the debris of damaged homes. Buildings were levelled while many people were still asleep.

Tremors were felt as far away as Lebanon, Greece, Israel, Iraq and the island of Cyprus.

Turkey is in one of the world’s most active earthquake zones, with land stretching over the Anatolian faultline in the north of the country that has caused large and destructive tremors.

İzmit and the surrounding Kocaeli region, close to Istanbul, were rocked by a 7.4-magnitude earthquake in 1999, the worst to hit Turkey in decades. That quake killed more than 17,000 people, including at least 1,000 in Istanbul, amid widespread destruction.

In Gaziantep, 150 miles from the border with Syria and 50 miles from the earthquake’s epicentre in Kahramanmaraş, residents were woken on Monday by violent shaking.

“We woke up with a jolt, as the electricity was off. We laid still and waited for the shaking to finish. Our house was full of broken glass,” said Sinan Şahan, a tradesperson, in Gaziantep. “We used our phone’s flashlight so we could get dressed, and hurried out of the house. Anyone able to save themselves has now fled somewhere.”

He added: “I was in Istanbul when the big earthquake hit in 1999; this is was more severe than that.” He broke off as another aftershock hit.

Images from Gaziantep appeared to show that the earthquake caused the collapse of the city’s historic castle, an ancient and imposing stone structure atop a hill used as an observation point during Roman times.

The head of the Turkish Red Crescent, the biggest humanitarian organisation in Turkey and part of the International Red Cross, said the group had mobilised resources for the region and urged people to evacuate damaged homes.

Images on Turkish television showed rescuers digging through the rubble of levelled buildings in the city of Kahramanmaraş and neighbouring Gaziantep, where entire high-rise blocks were destroyed. Buildings also crumbled in the cities of Adıyaman, Malatya and Diyarbakır, where people rushed out on the street in panic.

The Syrian health ministry reported damage across the provinces of Aleppo, Latakia, Hama and Tartus, on the Mediterranean coast.

The Turkish president, Recep Tayyip Erdoğan, will be under pressure to oversee an effective response to the disaster heading to an election on 14 May.

Pledges of assistance came in on Monday from countries across Europe, Asia and the Middle East, as well as North America. Turkey said it had received offers of aid from 45 governments ranging from Kuwait to India to Russia.

It was not clear what offers Turkey or Syria had agreed to. The UK announced it was sending a team of 76 search and rescue specialists, equipment and rescue dogs to Turkey. Separately, Moscow said rescuers were departing by plane to Syria.

Even before the tragedy, buildings in Aleppo, Syria’s prewar commercial hub, often collapsed due to the dilapidated infrastructure after more than a decade of war as well as little oversight to ensure safety of new construction projects, some built illegally.

The Syrian Civil Defence, a rescue service known as the White Helmets that works to save those trapped under debris from airstrikes, said it had declared a state of emergency to rescue the many people feared trapped under collapsed buildings in areas around Idlib and across opposition-held areas in north-western Syria.

Related: ‘There is nothing left’: earthquake adds to suffering in war-torn Syria

In a statement, the organisation described “a catastrophic situation with buildings collapsed or suffering major cracks, hundreds injured and stranded, dozens dead and a lack of services as well as safe shelters and assembly points in stormy and snowy weather conditions and low temperatures”.

The group also added a plea for aid from the international community “to prevent the situation from worsening” and to pressure the Syrian government and their backers in Moscow to hold back on airstrikes in the area to prevent further tragedy.

Several hundred miles from the epicentre, people in Damascus, as well as in the Lebanese cities of Beirut and Tripoli, ran into the street on foot and took to their cars to get away from their buildings in case of collapses, witnesses said.

“Paintings fell off the walls in the house,” said Samer, a resident of Damascus, the Syrian capital. “I woke up terrified. Now we’re all dressed and standing at the door.”

Aid groups fear the disaster will worsen the situation for Syrians already displaced after a decade of civil war.

“Millions have already been forced to flee by war in the wider region and now many more will be displaced by disaster,” said Carsten Hansen, of the Norwegian Refugee Council. “In the midst of a winter storm and an unprecedented cost of living crisis, it is vital that Syrians are not left to face the aftermath on their own.”

Reuters, Agence France-Presse and Associated Press contributed to this report