The US Coast Guard is “actively pursuing” another vessel in international waters near Venezuela as tensions continue to rise in the region.
US authorities have already seized two oil tankers this month – one of them on Saturday.
Sunday's pursuit was linked to a “sanctioned dark fleet vessel that is part of Venezuela's illegal sanctions evasion,” a U.S. official said. “It is operating under a false flag and is under a court seizure order.”
Washington has accused Venezuela of using oil money to finance drug crimes, and Venezuela has called the tanker seizures “theft and kidnapping.”
US President Donald Trump last week ordered a “blockade” of oil tankers entering and leaving the country.
Venezuela, home to the world's largest proven oil reserves, has accused the Trump administration of trying to steal its resources.
US authorities have not yet officially confirmed Sunday's pursuit, and the exact location and name of the tanker are still unknown.
As of last week, more than 30 of the 80 ships in Venezuelan waters or approaching the country were under U.S. sanctions, according to TankerTrackers.com.
Saturday's hijacking saw the Panamanian-flagged tanker boarded by a specialized tactical team in international waters.
The vessel is not on the U.S. Treasury Department's list of sanctioned vessels, but the U.S. said it was carrying “PDVSA-sanctioned oil.” The ship has also sailed under the Greek and Liberian flags in the past five years, according to BBC Verify records.
“These actions will not go unpunished,” the Venezuelan government said in response to Saturday’s incident. He added that he intends to file a complaint with the UN Security Council and “other multilateral agencies and governments around the world.”
Venezuela is heavily dependent on oil export revenues to finance its government spending.
In recent weeks, the US has increased its military presence in the Caribbean and carried out deadly strikes on suspected Venezuelan drug-smuggling vessels, killing about 100 people.
Sanctions have also been imposed on some of President Maduro's relatives and businesses linked to what the US calls his illegitimate regime.
Secretary of State Marco Rubio told reporters Friday: “It is clear that the current status quo with the Venezuelan regime is intolerable for the United States.”
He added that the Trump administration's goal is to change that dynamic.
His comments were criticized by Venezuela's foreign minister, who accused Rubio of dragging the US down the path of “regime change.”
It has provided no public evidence that the ships were carrying drugs, and the military has come under intense scrutiny from Congress over the strikes.
The Trump administration has accused Venezuelan President Nicolas Maduro of leading a designated terrorist organization called the Cartel de los Soles, which he denies.
