The explosion late Sunday near the town of Dogubayazit, close to the border with Iran, damaged the pipeline, forcing authorities to cut the gas flow, a statement from the pipeline company, Botas, said.
It was not immediately clear what caused the explosion. Separatist Kurdish rebels have attacked pipelines close to the border with Iraq and Iran in the past as part of their campaign for autonomy.
Repairs to the pipeline were under way, the statement said. Botas did not say when the pipeline would be operational, but said gas supplies to clients would not be affected.
Iran is a major supplier of natural gas to Turkey, after Russia.
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