The ship loaded with five million liters (one million gallons) of petrol was boarded 14 nautical miles off Zuwara and diverted to the naval base in Tripoli, he said.

Libya’s coast guard said Thursday it had intercepted a Russian-flagged tanker suspected of carrying an illegal shipment of petrol and detained 12 crew members from Russia.

“We received a signal on the presence of a ship transporting an illegal cargo of petrol near Zuwara,” 160 kilometers (100 miles) west of Tripoli, on Wednesday, Captain Taoufik Mohamad Assakir, operations chief for central Libya, told AFP.

The ship loaded with five million liters (one million gallons) of petrol was boarded 14 nautical miles off Zuwara and diverted to the naval base in Tripoli, he said.

The captain said its 12 Russian crew, including a woman, were detained.

In March 2014, the U.S. Navy intercepted and boarded the North Korean tanker “Morning Glory” loaded with an illegal oil shipment in the eastern Mediterranean and escorted it back to Libya, although it later escaped back to sea.

Libya has been plunged into insecurity and chaos since dictator Moamer Kadhafi’s ouster in a 2011 revolution, torn between an administration in Tripoli and the internationally recognised government in the oil-rich country’s far east.

The Tripoli authority controls vessels monitoring most of the country’s Mediterranean coast except for sections of the far east.