Hundreds of people have been reported dead after a major earthquake struck southeast Turkey and northern Syria, but it is expected that many more casualties will be identified once the actual toll of the catastrophe is revealed in the morning.
By 6.30 a.m. UK time, Turkey's dead toll had risen to 360, while Syria's health ministry said that at least 237 bodies had been found. Hundreds of thousands more individuals were injured.
The 7.8-magnitude earthquake last night was felt as far away as Cairo, and as aftershocks persisted on Monday morning, Italy issued a tsunami warning for coastal residents.
The previous time a quake of such magnitude struck Turkey, about 33,000 people were killed.
"I've never felt anything like that in my 40 years," Erdem, a native of the Turkish city of Gaziantep, told Reuters reporters.
"We were jolted at least three times, like a baby in a cradle.
Turkey's government issued a 'level four' warning, requesting international assistance and sent rescue personnel to comb through mountains of wreckage in search of individuals trapped beneath hundreds of fallen buildings.
Survivors' social media posts and photos of toddlers being pulled from the wreckage provided rays of hope:
The tragedy was exacerbated on the Syrian side, where deaths included individuals living in deplorable conditions with little access to healthcare.
According to local doctor Muheeb Qaddour, at least 11 people perished in the town of Atmeh, and many more were trapped under the wreckage.
"We dread hundreds of fatalities," Dr. Qaddour told The Associated Press, referring to the rebel-held northwest.
"We're under a lot of strain."
Homes and tent towns in opposition-held areas have collapsed, displacing four million people from other parts of the nation due to the long civil conflict.
"The situation is quite awful; tens of buildings have fallen in Salqin," a member of the White Helmets rescue organization stated in a video clip on Twitter, referring to a town about 5 km (3 miles) from the Turkish border.
Earlier, the preliminary death toll included 23 in Malatya province, 17 in Sanliurfa, six in Diyarbakir and five more in Osmaniye.
The US Geological Survey said the 7.8-magnitude quake was centered outside of Gaziantep, a major city and provincial capital in Turkey, just after 4am local time. It was followed by a 6.7 after shock about 10 minutes later.
The Survey had listed four subsequent tremors, of up to 5.6 magnitude.
Several buildings tumbled down in the neighboring provinces of Malatya, Diyarbakir and Malatya, HaberTurk television reported.
Injured people await treatment at the emergency ward of the Bab al-Hawa hospital in Syria's Idlib province.
Tremors also caused panic in Lebanon and Iraq.
In Beirut and Damascus, buildings shook and many people went down to the streets in fear.
Footage shared by people in Iraq showed hundreds of residents, many dressed in their pyjamas, and gathered in the dark outside apartment buildings as they awaited news on whether it was safe to return indoors.
Turkey sits on top of major fault lines and is frequently shaken by earthquakes.
Three years ago, 117 people died in a quake in the country's third-most populous city, Izmir. The quake with the highest number of fatalities in recent history was in 1999 when 17,127 were killed in the central Kocaeli province.
In 1939, a 7.8-magnitude quake killed 32,700 people in Erzincan.