Iranian forces have seized a chemical tanker in the Middle East on suspicion of smuggling oil, a day after US authorities claimed to have thwarted two other attempts by Tehran to detain tankers.

The incident took during the mid-afternoon period of Thursday.

A US Navy official said the company said Iran’s Islamic Revolutionary Guard Corps carried out the seizure.

Security company Ambrey said it had received a report that a Tanzania-flagged tanker of 1,131 dwt was approached by Iranian forces on Thursday.

Ambrey observed the vessel sailing at 5.6 knots and then increasing speed to 5.8 knots, carrying out two course changes within 16 minutes.

The tanker slowed down to 5.1 knots and continued sailing for an hour and 20 minutes, when it began to drift.

The company added that the tanker continued to drift at a maximum of two knots, in “a long-spread zig-zag course”, for the next five hours.

The description fits the profile of the 1,100-dwt Nada2 (built 1990).

The vessel was formerly known as Brave 2 and Hoei Maru No. 21

AIS data showed it underway off Iran at 4.1 knots at around 0400 GMT on Friday.

Iran later confirmed it had carried out an anti-smuggling operation against the vessel.

The tanker was sold by its Japanese owner in September 2022.

Its new ownership and management is said to be “opaque” by Ambrey.

Since September last year, the vessel has traded between Dubai and locations near Kuwait or Iraq.

US Naval Forces Central Command, which is based in Bahrain, deployed maritime assets to monitor the situation but decided the circumstances did not justify a further response.

“US forces remain vigilant and ready to protect navigational rights of lawful maritime traffic in the Middle East’s critical waters,” Commander Tim Hawkins, a Central Command spokesman, said in a statement provided to TradeWinds.

Iran has not commented on the incident, according to Qatari broadcaster Al Jazeera.

Diaplous said Iranian naval forces regularly intercept small tankers accused of smuggling oil.

“Iran is trying to stop widespread smuggling of oil and fuel by land and sea to Gulf states,” the firm said. “The smuggling has come as Iran’s currency has plunged under the pressure of US sanctions imposed after the collapse of Tehran’s 2015 nuclear deal with world powers.”

The incident comes a day after the US accused Iranian forces of attempting to seize two tankers, firing on Chevron’s 319,000-dwt Richmond Voyager (built 2018), which suffered minor damage.

Iran later claimed that it had a court order to seize the US oil company’s VLCC after it had collided with an Iranian vessel, as TradeWinds reported.

The Maritime Search and Rescue Centre of Iran’s Hormozgan Province said the country’s navy had obtained the order at the request of the Iranian shipowner, according to the official IRINN news agency.

Iran said five people were injured on the unnamed Iranian vessel, and the incident caused flooding on board.

“The Richmond Voyager was not involved in any collision,” Chevron spokeswoman Christine Dobbyn told TradeWinds.