Iran on Sunday seized a foreign-flagged vessel in the northern shores of the Persian Gulf, which it alleged was carrying 200,000 liters of "smuggled fuel".
In a statement, the Islamic Revolutionary Guard Corps (IRGC) Navy said eight members aboard the vessel were arrested and handed over to judicial authorities in Iran’s southern Bushehr port.
The source of the fuel tanker and the nationality of the arrested crew were not immediately known.
Gholamhossein Hosseini, the director of the IRGC Navy's public relations wing in Bushehr, said five other smaller vessels that intended to refuel the foreign-flagged tanker were also taken into custody for further investigations.
He said "fighting fuel smuggling" is among the IRGC Navy's "important priorities" in line with supporting the country's economy.
He also warned that the shores of the Persian Gulf "will not be a safe place for profiteers and smugglers".
Iran has seized many foreign-flagged oil tankers in its territorial waters in recent years on charges ranging from smuggling fuel to polluting the maritime environment.
In November last year, another foreign-flagged vessel was seized by the IRGC in the southern Hormozgan province, which borders the Persian Gulf and the Gulf of Oman, along with its 11-member crew.
The IRGC said the vessel was captured with more than 150,000 liters of "smuggled fuel".
A month before that, the IRGC seized a Vietnamese oil tanker in the Sea of Oman, which was released a week after following hectic negotiations between the two sides.
Iran accused the US of "stealing" the oil from the tanker but the US Department of State rejected the claim, saying the ship was seized while the US Navy was "monitoring the situation."
In January last year, in a case that grabbed international headlines, a South Korean-flagged vessel was seized by Iran in the Persian Gulf over an alleged "violation of maritime environmental laws".
While South Korean officials said the seizure of the vessel amounted to hostage-taking over Iran's frozen assets in Seoul, Iran said the issue should not be politicized. The ship and its crew were released three months later.