A 7.8 magnitude earthquake struck Turkey and neighboring Syria on Monday, killing over 3,400 people and injuring thousands more. The quake caused widespread destruction, resulting in thousands of buildings collapsing and trapping residents under the rubble. The death toll is expected to rise as rescue efforts continue in the region, which is already beset by Syria’s 12-year civil war and a refugee crisis.

Throughout the day, major aftershocks rattled the region, including one that was nearly as strong as the initial quake. Tens of thousands of people were left homeless and faced a cold night as they took refuge in shopping malls, stadiums, and community centers. The Turkish president declared seven days of national mourning.

The earthquake was centered in Turkey’s southeastern province of Kahramanmaras and was felt as far away as Cairo. The quake piled more misery on a region that has already seen tremendous suffering over the past decade. On the Syrian side, the area is divided between government-held territory and the last opposition-held enclave. The opposition emergency organization reported that hundreds of families in the rebel-held enclave were trapped in the rubble.

Strained health facilities quickly filled with injured, while others had to be emptied. Over 7,800 people were rescued across 10 provinces. The region sits on top of major fault lines and is frequently shaken by earthquakes. The U.S. Geological Survey measured the quake at 7.8 with a depth of 18 kilometers. A 7.5 magnitude temblor struck later in the day.

Offers of help poured in from around the world, including search-and-rescue teams, medical supplies, and money.