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Iran detained two oil tankers as they transited the strait of Hormuz but has released one of the vessels.
In the latest escalation of tensions along the vital shipping channel, Iran's Islamic Revolutionary Guard (IRGC) said it captured the UK-flagged Stena Impero "for breaching international maritime law." Iranian officials also briefly detained a second, Liberian-flagged tanker, the very large crude carrier (VLCC) Mesdar.
UK ship manager Norbulk Shipping said the "armed guards" that had boarded the Mesdar have left, allowing the vessel to continue on its voyage.
The 315,000 dwt Mesdar is unladen and was pointed toward Ras Tanura, Saudi Arabia, according to Argus analysis of vessel tracking data.
Calling the detentions "unacceptable," UK foreign secretary Jeremy Hunt said UK officials will be in contact with the Iranian Ministry of Foreign Affairs. "It is essential that freedom of navigation is maintained and that all ships can move safely and freely in the region," he said.
US president Donald Trump said the Iranians are "showing their colors." Yesterday he called on other nations to work with the US to protect ships as they move through the strait.
"This only goes to show what I am saying about Iran: trouble," Trump said. "Nothing but trouble."
The detentions came just a few few hours after the UK said it would hold onto an Iranian tanker it seized off Gibraltar earlier this month.
This is the latest in a series of confrontations in the Mideast Gulf that began with an attack on four tankers berthed outside Fujariah, UAE, in mid-May. Since then, two tankers have been attacked while traversing the strait of Hormuz; Iran shot down a US drone; and the US said yesterday that it shot down an Iranian drone.
Tanker owner Stena Bulk said the StenaImpero was approached by unidentified small crafts and a helicopter while in international waters, and it is now unable to make contact. There are 23 people on board. Tanker tracking showed the tanker, which typically transports clean product cargoes, diverted sharply from its heading of Jubail in Saudi Arabia and is moving north in the direction of Iran's Larak island — a holding point for the country's state-owned NITC fleet.
Earlier today Gibraltar's supreme court gave authorities there permission to detain the VLCC Grace 1 for an additional 30 days. It was seized on suspicion of taking crude to Syria, in breach of EU sanctions. Iran has laid claim to the Grace 1 and had threatened to retaliate in kind.
BP cancelled the charter of its Suezmax British Heritage through the strait earlier this month, and the UK government said three Iranian vessels attempted to impede it when it did pass through.