A powerful 7.3 magnitude earthquake rocked Turkey on Sunday, presumably killing hundreds of people in the city of Van.

State-run TRT television said the quake collapsed 80 buildings and at least 85 people have been confirmed dead three hours after the quake struck.

The US Geological Survey said the Turkey earthquake struck with a preliminary magnitude of 7.3, while Turkey's Kandilli observatory reported a preliminary magnitude of 6.6.

"The area where the earthquake occurred is very shallow," Mustafa Erdik, head of the Kandilli observatory, said in televised comments.

"Normally quakes happen 30 to 40 kilometers deep -- this is less than 10 kilometers, therefore there will be more damage," Erdik added.

Bloomberg News reported that Greek Foreign Minister Stavros Lambrinidis has spoken with his Turkish counterpart, Ahmet Davutoglu, to assured him that Greece was prepared to assist Turkey in this tragedy.

Reports say this is Turkey's strongest and biggest quake in over a decade.