The accident occurred at around 3:45 a.m. on the highway stretching between Konya's Ereğli district and Adana as a passenger bus traveling from İzmir to Hatay lost control and crossed into the opposite direction despite guardrails.
Meanwhile, another passenger bus traveling from the southeastern province of Diyarbakır to the Aegean town of Bodrum failed to stop, striking the first vehicle.
Reports indicate both drivers lost control due to ice.
According to initial reports from the scene, six passengers from both buses died while some 24 passengers were injured.
The wounded persons were transferred to nearby hospitals while the highway remains closed to traffic due to the accident.