Twelve migrants froze to death after being stripped of their clothes and 'pushed back' by Greek border guards, Turkey's interior minister said on Wednesday.
The charges from Interior Minister Suleyman Soylu threaten to escalate simmering tension between the rival members of the NATO defence alliance.
They also highlight Ankara's concern that the European Union was not doing enough to support Turkey -- which hosts an estimated five million migrants and refugees -- in the face of a potential new flow of people from Afghanistan.
Soylu posted blurred images on Twitter showing bodies lying by the side of the road.
"Twelve of the 22 migrants pushed back by Greek border units" have frozen to death after being "stripped (of) their clothes and shoes", Soylu wrote in English.
The "EU is remediless, weak and void of humane feelings", he added.
Soylu said the pictures were taken near Turkey's western border town of Ipasala.
The regional governor's office said 11 of the migrants were discovered frozen to death.
Another migrant who was rushed to hospital with severe frostbite "could not be saved and died", the governor's office said.