The death toll from a magnitude 7.8 earthquake that struck the southeastern region of Turkey along the border with Syria has continued to rise.

    The first earthquake struck on Monday morning at 4:17am (01:17 GMT) and was centred in the Pazarcik district of Kahramanmaras Province.

    According to the United States Geological Service (USGS), the earthquake struck at a depth of about 17.9km (11 miles). Turkey’s Disaster and Emergency Management Authority (AFAD) put the magnitude of the quake at 7.4 near the cities of Kahramanmaras and Gaziantep.

    Dozens of aftershocks were recorded following the quake with officials urging people not to enter damaged buildings due to the risks.

Less than 12 hours later, a second 7.6 magnitude tremor struck the same region.

    In a statement carried by the state-run Anadolu Agency, AFAD listed the affected regions so far as Kahramanmaras, Gaziantep, Sanliurfa, Diyarbakir, Adana, Adiyaman, Malatya, Osmaniye, Hatay and Kilis. Thousands more have been affected across the border in the Syrian provinces of Aleppo, Idlib, Hama, and Latakia.

    At least 3,381 deaths have been reported in Turkey, while 1,444 people have died in Syria. The death toll is likely to keep rising.

    Yunus Sezer, who heads the AFAD agency, said an additional 15,384 people were injured in Turkey, while 6,217 buildings have collapsed.

    The two quakes were followed by 243 aftershocks, he said, adding that 16,400 rescue workers were active in the affected areas.

    Turkish President Recep Tayyip Erdogan said on Twitter that “search and rescue teams were immediately dispatched” to the areas hit by the quake. “We hope that we will get through this disaster together as soon as possible and with the least damage,” he wrote.

    Al Jazeera’s Sinem Koseoglu, reporting from Istanbul, said bad weather across the country could hinder search and rescue efforts in areas affected by Monday’s earthquake.

    “The flights from Istanbul and Ankara to eastern Turkey have been cancelled because of wind, rain and snow in Istanbul and heavy snow in Ankara. So we cannot easily access the affected areas,” she said.

    “And in eastern Turkey, in Gaziantep, there is heavy snow. And in Kahramanmaras, there is rain. Our colleagues and friends in the area say they are outside, in the cold, and that they are afraid to go inside their buildings.” she added.

    The earthquake’s epicentre is home to millions of Syrian refugees living in Turkey outside the city of Gaziantep.

    Thousands of residents have been left without shelter in freezing temperatures. Temperatures are expected to drop below freezing by Tuesday, with the low in Gaziantep falling to -6 Celsius (21 Fahrenheit).

    Turkey is in one of the world’s most active earthquake zones. Monday’s 7.8 magnitude earthquake is the most powerful to hit the country since 1999.

    In August 1999, a powerful magnitude 7.6 earthquake shook Marmara, a densely populated region to the south of Istanbul, Turkey’s largest city, for 45 seconds. Within days, the official death toll stood at 17,500.