Satellite photos showed Dominica-flagged vessel in Iranian waters on Tuesday.

An oil tanker sought by the United States over allegedly circumventing sanctions on Iran was hijacked on July 5 off the coast of the United Arab Emirates, a seafarers’ organisation said on Wednesday.

Satellite photos showed the vessel in Iranian waters on Tuesday.

It was not immediately clear what happened on board the Dominica-flagged MT Gulf Sky, though its reported hijacking comes after months of tensions between Iran and the US.

David Hammond, CEO of the United Kingdom-based Human Rights at Sea, said he took a witness statement from the captain of the MT Gulf Sky, confirming the ship had been hijacked.

Hammond said 26 of the Indian sailors on board had made it back to India, while two remained in Tehran, without elaborating.

Hammond said he had no other details on the vessel.

TankerTrackers.com, a website tracking the oil trade at sea, said it saw the vessel in satellite photos on Tuesday in Iranian waters off Hormuz Island.

Hormuz Island, near the port city of Bandar Abbas, is some 190km (120 miles) north of Khorfakkan, a city on the eastern coast of the UAE where the vessel had been for months.

In May, the US Justice Department filed criminal charges against two Iranians, accusing them of trying to launder some $12m to buy the tanker, then named the MT Nautica, through a series of front companies.

The vessel then took on Iranian oil from Kharg Island to sell abroad, the US government said.

Court documents allege the scheme involved Iran’s Islamic Revolutionary Guard Corps’ Quds Force, which is its elite expeditionary unit, as well as Iran’s national oil and tanker companies.

The two men charged, one of whom also has an Iraqi passport, remain at large.

Data from the MT Gulf Sky’s Automatic Identification System tracker shows it had been turned off at approximately 4:30am on July 5, according to ship-tracking website MarineTraffic.com.

As tensions between Iran and the US heated up last year, tankers plying the waters of the Middle East became targets, particularly near the crucial Strait of Hormuz, the Gulf’s narrow mouth through which 20 percent of all oil passes.

Suspected limpet mine attacks the US blamed on Iran targeted several tankers. Iran denied being involved, though it did seize several tankers.