Gibraltar police have arrested two more crew members of the Iranian oil supertanker seized by British marines and local law enforcement last week.

The men detained on Friday are two second mates, both Indian nationals, local daily the Gibraltar Chronicle reports, citing the police. The men have been questioned but have not faced any charges yet, the paper says, adding that they “are assisting police” with its probe.

The development follows the arrests of the ship’s captain and chief officer on Thursday, who were detained on suspicion of breaching EU sanctions against Syria.

Also on rt.com Gibraltar police arrest Iranian tanker’s captain, chief officer

The Panama-flagged and Singapore-owned oil supertanker was seized near the Strait of Gibraltar last week. The US said that the captured ship was transporting Iranian oil while the UK suspected it was carrying oil to Syria in violation of restrictions imposed by the EU.

Tehran acknowledged its ties to the vessel but denied it was heading to Syria. Iran also demanded an immediate release of the tanker, warning of “consequences” otherwise. London, meanwhile, raised the ship security code for all British-flagged vessels passing near Iran’s territory to the highest level.

On Thursday, it said that a group of Iranian patrol boats sought to impede the passage of the British tanker operated by BP through the Strait of Hormuz.

Tehran dismissed those accusations.Iran also branded the UK’s seizure of the tanker as “piracy” while saying that London was acting on behalf of Washington. The development, indeed, comes amid an ongoing bitter standoff between the US and Iran, which saw Washington leaving the 2015 Iranian nuclear deal, re-imposing sanctions against the Islamic Republic and repeatedly vowing to bring Iranian oil exports down to “zero.”

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