The Islamic Revolution Guard Corps' Navy has seized two vessels carrying 1.5 million liters of smuggled fuel in the waters of Mashahr in southwestern Iran.

Admiral Mohammad Sharif Shirali, Deputy Commander of the Third Naval Zone of the IRGC, said in an interview with the Fars news agency that the IRGC's Navy stopped the two ships for smuggling oil, as part of an Iranian intelligence and surveillance operation.

The operation lasted two days as officers monitored and surveyed the area before capturing the ships.

The vessels, which held the Panamanian flag, attempted to sail away from Iran with a crew of 37 individuals from multiple nationalities.

US steals Iranian oil

Earlier on September 9, the United States Department of Justice (DoJ) confirmed that the US looted a tanker load of Iranian oil in April.

The DoJ's first official statement on the incident mentioned on its website that the government had seized the Suez Rajan, a Greek-managed tanker, and its cargo of 980,000 barrels of crude oil, allegedly being sold by the IRGC to China.

The statement claimed that the sale violated US and international sanctions and that the US government obtained a warrant early this year for its seizure.

On April 19, around the time of the seizure, the vessel's owner, Suez Rajan Ltd, pleaded guilty to sanctions violations and was fined $2.5 million.

Subsequently, the Greek vessel operator, Empire Navigation, agreed to cooperate with US authorities and ordered the ship, located in Southeast Asia at the time, to take its load of oil to the United States.

At the time, US authorities would not confirm it was seizing the cargo and that the ship was sailing to the United States.

A few days later, Iran seized two tankers. The first was the Marshall Islands-flagged Advantage Sweet, which violated international and navigation laws as it sailed toward the United States in the Gulf of Oman. The second was the Greek-owned Niovi over a private complaint and a consequent order by judicial authorities as it traveled from Dubai to Fujairah.

The IRGC has ramped up its naval force in the face of US incursions on maritime activity in the Gulf, including the facilitation of smugglers' operations.

Iranian Foreign Ministry Spokesperson Nasser Kanaani said earlier in August that Iran would not remain idle concerning the piracy acts against tankers carrying Iranian oil.

"Acts of trespassing on tankers carrying Iranian oil are a clear example of piracy," Kanaani was quoted by Fars as saying. "Iran will not stand idly by in relation to any violation of the nation's rights and will cut the hands of the aggressors."

Read more: Why US oil firms are too afraid to unload seized Iranian oil: WSJ