Iran Has Followed Through With Its Threat To Capture A British Tanker In The Middle East (Updated)

Iran has been threatening for weeks to retaliate for U.K. officials detaining one of its supertankers over sanctions violations.

byJoseph Trevithick|
Iran photo


Iran's Islamic Revolutionary Guard Corps, or IRGC, says that it has seized the British-flagged tanker Stena Impero in the Strait of Hormuz. This follows threats to retaliate over U.K. authorities seizure of the Iranian supertanker Grace 1 off the coast of Gibraltar earlier this month. It is also the latest in a string of incidents involving Iran in the region, including the U.S. military downing an Iranian drone in the Strait and the IRGC's admission that it had seized a Panama-flagged tanker on suspicion of fuel smuggling, both of which occurred just yesterday.

Ship spotters using online tracking software first came to suspect Iranian forces had captured Stena Impero after it abruptly changed its course earlier on July 19, 2019, and began sailing toward Iran's Qeshm Island. The tanker's stated destination had been Al Jubail in Saudi Arabia. The IRGC subsequently announced that it had taken control of the ship. Northern Marine Management, a U.K.-based subsidiary of Swedish Company Stena AB, which owns the ship, also confirmed that the Iranians had seized the tanker and its 23 crew members after approaching it with small boats and a helicopter.

The IRGC has said that it detained Stena Impero "for breaching international maritime law" as it transited the Strait of Hormuz, but has not provided any further explanation so far for this justification or evidence of the ship's purportedly illicit behavior. Iran has been threatened to seize a British tanker or otherwise engage in some form of tit-for-tat retaliation against the United Kingdom over the Grace 1, which has been impounded in Gibraltar since July 4, 2019, over sanctions violations.

Iran denies that Grace 1 was heading to Syria as the United Kingdom alleges, which would violate European Union sanctions, but Iranian authorities have not offered any evidence of an alternative destination. On July 19, 2019, British officials had extended the detention of Grace 1 for another 30 days, which drew criticism from Iran, which claimed the decision contravened promises from U.K. Foreign Minister Jeremy Hunt to release the tanker. However, Hunt had publicly stated that this would only be possible if Iran could provide verifiable assurances that the ship's final destination was not Syria.

On July 10, 2019, IRGC fast boats had harassed the British-flagged tanker British Heritage in the Strait of Hormuz, but were warned off by the Royal Navy's Type 23 frigate HMS Montrose, which was escorting it at the time. It is unclear whether Stena Impero had an escort at the time of this incident, but this would appear to have not been the case. The Royal Navy had announced recently that it was sending the Type 45 destroyer HMS Duncan to the Middle East to take the place of the Montrose

in a routine swap-out.

So far, the British Ministry of Defense publicly says that it is seeking more information about the circumstances surrounding the IRGC's detention of Stena Impero. There are unconfirmed reports that the U.K. government has convened a so-called Cabinet Office Briefing Rooms meeting, or COBRA, something that occurs to bring top officials together to discuss responses to major national crises.

Tensions in the region have been steadily rising between Iran and various countries, especially the United States, for months now, in general. On July 19, 2019, the IRGC admitted that it had detained another tanker, the Panama-flagged Riah, on July 14, 2019. This came after the Iranian Foreign Ministry claimed that Iranian forces had towed this ship into the country's territorial waters after it experienced a technical fault and issued a distress call. The circumstances surrounding that incident remain murky.

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Later that same day, the United States also announced that U.S. Marines on board the U.S. Navy's Wasp-class amphibious assault ship USS Boxer had brought down an Iranian drone with a vehicle-mounted anti-drone electronic warfare system while sailing through the Strait of Hormuz. Subsequent reports indicated that a number of Iranian aircraft and boats had also harassed the Boxer and other ships in its convoy as they transited the area.

Iran has denied losing a drone and has since released footage from what appears to be a fixed-wing Mohajer series drone, judging by the landing skids visible in the video clips, flying over the ships. Details in the footage align with pictures the U.S. Navy has released itself and also adds weight to the United States' assertion that the unmanned aircraft, as well as Iranian helicopters, had flown relatively close to the ship during the incident.

We will continue to update this story as more information becomes available.

UPDATE: 3:20pm EST—

There is the possibility that Iran may be in the process of seizing a second tanker, the U.K.-owned, but Liberian-flagged Mesdar. So far, there does not appear to be an official confirmation from the IRGC that it has detained another ship.

A White House spokesperson also told the BBC that the U.S. government was aware of the still-developing situation. "The U.S. will continue to work with our allies and partners to defend our security and interests against Iran's malign behavior," they added in their statement. 

UPDATE: 3:25pm EST—

U.S. President Donald Trump has told reporters that he has heard reports that a second tanker might have been seized, but does not confirm or deny that this is the case. He also did not say how the United States might respond to the incident.

UPDATE: 3:30pm EST—

CNN is now reporting, citing anonymous U.S. defense officials, that the IRGC has also seized Mesdar.

UPDATE: 4:05pm EST—

According to CNN, citing unnamed U.S. defense officials, at least one unspecified U.S. military aircraft is providing armed overwatch for a U.S. cargo ship passing through the Strait of Hormuz.

There had also been an indication that Iranian forces might have seized a third tanker, but the behavior of LR2 Posiedon does not match that of either Stena Impero or Mesdar during their captures.

In addition, The Telegraph newspaper in the United Kingdom is reporting that there are no British nationals on board Stena Impero. It is not clear whether or not this is the case with Mesdar, but the multi-national makeups of their crews could turn the situation into a broader international incident. Russian nationals, for instance, are among Stena Impero's crew.

UPDATE: 4:15pm EST—

Mesdar's transponder has reportedly come back on and indicates that the ship is moving away from Iran. The Iranians now deny that they had detained it and claim they had simply stopped it to inform its crew of environmental and maritime regulations in the area.

Iran has now also claimed that it detained Stena Impero had left the designated shipping lane, turned off its transponder, and refused to respond to Iranian warnings. This would directly conflict with the publicly available tracking information from the ship's transponder that show it slowing, stopping, and then turning toward Iran.

In the meantime, it appeared that HMS Montrose, or one of the Sandown class minehunters the Royal Navy has in the region, arrived on the Strait of Hormuz. possibly to begin a patrol to try to prevent and further seizures from occurring. However, the ship then abruptly turned around and began heading in the opposite direction.

UPDATE: 5:50pm EST—

U.K. Foreign Minister has warned that Iran will face unspecified consequences if it does not release the Stena Impero, but has said his country is not considering military options at this time. He added that Iran would be the "biggest loser" if it decided to restrict freedom of navigation in the Strait of Hormuz.

The U.S. Department of Defense has also now issued a statement saying that unarmed, rather than armed aircraft are monitoring the situation.

Separately, there have been unconfirmed reports that Iran may be planning to begin routinely boarding and inspecting foreign oil tankers ostensibly to ensure compliance with environmental regulations. This could make it difficult for ships to avoid seizure in the future, as failing to stop for such a check could also give Iranian authorities a pretext to detain a ship. 

UPDATE: 8:50pm EST—

In light of today's events, the United Kingdom has issued an advisory warning all U.K. shipping to avoid the Strait of Hormuz for an "interim period." 

U.S. Central Command has also issued a statement regarding Operation Sentinel, a new multi-national effort to "ensure freedom of navigation in light of recent events in the Arabian Gulf region," which has been in the works for some time already. 

The full statement is as follows:

"U.S. Central Command is developing a multinational maritime effort, Operation Sentinel, to increase surveillance of and security in key waterways in the Middle East to ensure freedom of navigation in light of recent events in the Arabian Gulf region. 

The goal of Operation Sentinel is to promote maritime stability, ensure safe passage, and de-escalate tensions in international waters throughout the Arabian Gulf, Strait of Hormuz, the Bab el-Mandeb Strait (BAM) and the Gulf of Oman. 

This maritime security framework will enable nations to provide escort to their flagged vessels while taking advantage of the cooperation of participating nations for coordination and enhanced maritime domain awareness and surveillance.

While the United States has committed to supporting this initiative, contributions and leadership from regional and international partners will be required to succeed. 

U.S. officials continue to coordinate with allies and partners in Europe, Asia, and the Middle East on the details and capabilities required for Operation Sentinel to enable freedom of navigation in the region and protect vital shipping lanes."

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