Iran seizes two Greek tankers in Persian Gulf, tensions spike

DUBAI, United Arab Emirates -- Iran's paramilitary Revolutionary Guard seized two Greek oil tankers on Friday in the Persian Gulf, just after Athens assisted the U.S. in seizing an Iranian oil tanker over alleged sanctions violations in the Mediterranean Sea.

The Guard's announcement comes as tensions remain high between Iran and the West over stalled negotiations regarding its rapidly advancing nuclear program.

The Guard issued a statement on its website, accusing the unnamed tankers of unspecified violations.

Greece's Foreign Ministry said it made a strong demarche to the Iranian ambassador in Athens over the "violent taking over of two Greek-flagged ships" in the Persian Gulf.

"These acts effectively amount to acts of piracy," a ministry statement said.

The ministry called for the immediate release of the vessels and their crews, and said these acts would have "particularly negative consequences" in bilateral relations and in Iran's relations with the European Union, of which Greece is a member.

The ministry's statement said that earlier Friday, an Iranian helicopter landed on the Greek-flagged Delta Poseidon in international waters some 22 nautical miles off the coast of Iran.

"Armed men then took the crew captive," it said, adding that two Greek nationals were among the crew.

"A similar incident has been reported on another Greek-flagged vessel, that was carrying seven Greek citizens, close to the coast of Iran," the ministry said.

It did not identify the nationalities of the other crew onboard the vessels.

A U.S. defense official, speaking on condition of anonymity to discuss intelligence matters, said it appeared the two ships had come close to -- but not in -- Iranian territorial waters Friday before drifting off into Iranian waters. The ships also had turned off their tracking devices, another red flag, the official said. However, neither had issued a mayday or a call for help, the official said.

Iran had threatened to take "punitive action" earlier Friday over Athens being involved in the U.S. seizure of an Iranian oil tanker in Greek waters.

Iran's Nour News website, close to its security services, made the threat just as shipping news site Lloyd's List said it believed two Greek tankers had been seized in the Persian Gulf. Quoting anonymous industry sources, Lloyd's reported that the two ships had been boarded after Iranian military helicopters approached them on Friday afternoon. It said both tankers had just been loaded with Iraqi crude oil.

The crude oil cargo of an Iranian-flagged tanker that was stopped in Greek waters last month has been seized and is being transferred to another vessel following a request from the United States, a Greek official said Thursday.

The official said following a "judicial intervention by U.S. authorities concerning the ship's cargo" the process is currently underway, at U.S. government expense, for the oil "to be handed over" off the port of Karystos on the Aegean Sea island of Evia.

The official, who asked not to be identified in order to discuss the case, did not provide further details. A Justice Department spokesman in Washington and the U.S. Embassy in Athens declined to comment Thursday.

Paphitis reported from Athens, Greece. Associated Press writer Amir Vahdat in Tehran, Iran, contributed to this report.