The head of Syria's National Earthquake Center, Raed Ahmed, told local media that this was "historically, the biggest earthquake recorded in the history of the center."
NW #Syria in a state of catastrophe after 7.8 magnitude #earthquake. Destruction, devastation, and collapse of buildings. Hundreds of injuries, dozens of deaths, many trapped under the rubble or stranded in the winter cold. We call on the international community to take action. pic.twitter.com/rtzqRJa8IP
The White Helmets rescue organization said buildings also collapsed in the rebel-held areas of northwestern Syria, adding that the situation was "disastrous."
The region is one of the world's most active earthquake zones.
Thousands of people were killed and many more displaced when a 7.6 magnitude earthquake struck the western city of Izmit in 1999.
In 2011, more than 500 people were killed by a 7.1 magnitude earthquake in the eastern city of Van.
Offers of support
Meanwhile countries have come forward to offer assistance with White House National Security Adviser Jake Sullivan saying the US was ready to help in rescue efforts.
President of Ukraine Volodymyr Zelenskyy sent a message of support and also offered assistance.
"I am shocked to learn of deaths and injuries of hundreds of people as a result of the earthquake in Turkey," Zelenskyy wrote in a tweet. "At this time, we stand by the friendly Turkish people and are ready to provide the necessary assistance,'' Zelenskyy said.
Israel's Defense Minister Yoav Gallant also said his country was prepared to provide any assistance if needed.