A massive earthquake has struck a large area in southeast Turkey, close to the border with Syria, killing more than 500 people and trapping a large number of others.

According to Vice President Fuat Oktay, at least 284 people were murdered and more than 2,300 were injured in Turkey. At least 237 people were killed and another 630 were injured in neighboring Syria, according to the Syrian state news agency SANA, which cited a Ministry of Health official.

The 7.8-magnitude earthquake occurred shortly after 4:00 a.m. local time on Monday, 23 kilometers (14.2 miles) east of Nurdagi, Gaziantep province, and at a depth of 24.1 kilometers (14.9 miles), according to the United States Geological Survey (USGS). The quake was felt in various countries in the region, including Syria and Lebanon. Nurdagi is located on the border between Turkey and Syria.

Dozens of people are reportedly buried under rubble, as reported by the "White Helmets" group, also known as Syria Civil Defense, a humanitarian organization founded to rescue conflict-related casualties. A large portion of northwestern Syria, which borders Turkey, is under the control of anti-government forces as a result of the 2011 civil conflict.

Monday morning, before sunrise, residents were likely asleep and unprepared for the earthquake. In a video from Turkey that was uploaded on social media, scores of buildings had collapsed, and terrified citizens were gathered in the streets' darkness amid the turmoil. The use of flashlights to conduct search-and-rescue operations by rescue personnel.

Strong aftershocks have been felt in the southern and central regions of Turkey. 11 minutes after the main earthquake, the strongest aftershock of magnitude 6.7 occurred 32 kilometers (20 miles) to the northwest of the epicenter of the main earthquake. 19 minutes after the initial quake, another severe aftershock with a magnitude of 5.6 occurred.

Turkey's interior minister, Suleyman Soylu, stated that search and rescue teams had been dispatched to the south of the country. AFAD, the disaster agency, announced that it had requested international assistance through the Emergency Response Coordination Centre (ERCC), the humanitarian program of the European Union.

According to its governor, Ali Yerlikaya, about a thousand search and rescue volunteers have been dispatched from Istanbul, the largest city in Turkey, along with dogs, trucks, and supplies.

"Sorry for our loss. I wish our injured a speedy recovery," Yerlikaya wrote on Twitter.

According to the USGS, Monday's earthquake was the largest to strike Turkey since 1939, when a quake of the same magnitude killed 30,000 people. Fewer than five earthquakes of this size occur annually, on average, in any part of the world. In the past 25 years, seven earthquakes of magnitude 7.0 or larger have rocked Turkey, but Monday's is the strongest.