WASHINGTON — Iranian navy vessels harassed a US-flagged merchant ship days before it detained a ship flagged to the Marshall Islands, the Pentagon confirmed today, the latest news in a tense stand-off between Iran and the US.

The US destroyer Farragut and three patrol ships craft continued to observe on Wednesday in the vicinity of the Marshall Islands-flagged Maersk Tigris, a day after it was fired upon, seized and boarded. The Tigris, which had been led from an internationally recognized shipping lane in Iranian waters, remained at anchor off Larak Island, in the Strait of Hormuz.

"What they're doing is keeping an eye on things," Col. Steven Warren, Pentagon spokesman, said of the US vessels. "They're in close enough proximity to respond if a response is required."

Along with the Farragut, a guided missile destroyer, are Cyclone-class coastal patrol ships Thunderbolt, Firebolt and Typhoon—all based at Bahrain. Since receiving a distress call from the Tigris on Tuesday, the US vessels are conducting maritime security operations and monitoring the situation.

The coastal patrol boat Firebolt.

Photo Credit: William H. Clark/Navy

Although the ships are not within sight of the Tigris, the US is monitoring with its patrol and reconnaissance aircraft aviation assets.

"If there is a requirement for protection to be executed, the Farragut is prepared to fulfill that requirement," Warren said.

With the Tigris in Iranian waters, it was unclear what the US response might be. Warren said the US government remained in discussions with the Marshall Islands, which the US is obligated by treaty to defend, about the response. That responsibility includes Marshallese vessels, Warren said.

The response, "would obviously be a presidential decision and we have to look into specifically what that compact says," Warren said. "My understanding is that [the US-Marshall Islands treaty] contains a provision that says the United States has discretion as to what actions to take."

The Defense Department does not have communications with Iran, and Iran's motives are, "not clear to the Department of Defense," Warren said.

"It's difficult to know why the Iranians are operating this way," Warren said. "We certainly call on them to respect all of the internationally established rules of freedom of navigation, the Law of the Sea, to which they are a signatory, and other established protocols."

Maersk on Wednesday released a statement saying the Tigris is a time-charter vessel and on-hire to Maersk through Rickmers Shipmanagement, a Singapore company a division of the Rickmers Group.

"Our paramount concern is the safety and well-being of the crew," said Maersk spokesman Timothy Simpson. "We are working in close dialogue with Rickmers Shipmanagement to obtain information about the seizure and explore options to help resolve this situation. We are also in dialogue with the Danish Ministry of Foreign Affairs."

Warren confirmed that on April 24, four patrol boats with the Iranian Revolutionary Guard Corps Navy harassed the Maersk Kensington. The Iranian boats came astern of the US-flagged container vessel and followed her for 15 to 20 minutes, "in actions that the ship's master of the Kensington interpreted as aggressive," Warren said.

"Certainly they have harassed two ships in the Straits, two is a pattern in a matter of four or five days," Warren said. "It certainly created a situation where maritime cargo vessels would have to consider the risks of traversing that strait."

According to Maersk, the incident happened about 30 nautical miles north by northwest of Dubai, and there was no communication between the gunboats and the Kensington. The Kensington was en route from Jebel Ali, in the UAE, to Jawaharlal Nehru Port, south of Mumbai, India.

The Iranian ships did not try to board the Kensington, and there was no US Navy involvement until after the incident, when the ship's master filed a report with US Navy Central, Warren said.

Warren could not say whether the Maersk Kensington was operating under a charter from military sealift command or carrying military cargo. Nor could Warren say whether the Tigris was carrying military cargo, though he said he did not know.

Email: jgould@defensenews.com

Twitter: @reporterjoe

Joe Gould is the Congress and industry reporter at Defense News, covering defense budget and policy matters on Capitol Hill as well as industry news.

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