Three suspects were arrested after 5.2 million liters (around 1.4 million gallons) of smuggled fuel was seized in operations in central and southern Turkey, a security source said on Friday.

The seizure was the largest ever in Turkey’s history, the source said on condition of anonymity due to restrictions on speaking to the media.

Police in Konya acted on a tip-off to seize 12,000 liters (around 3,170 gallons) of smuggled fuel, the source said.

The operation in Konya led authorities to the source in the southern Mersin province, where over five million liters (1.3 million gallons) of smuggled fuel

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