The US military is holding two individuals aboard a Navy ship in the Caribbean after two others on their vessel were killed in a targeted US strike, sources told news agencies on Friday.

The US has conducted several strikes on what it calls "narcoterrorist" vessels off the coast of Venezuela since September, with US President Donald Trump accusing Venezuela's President Nicholas Maduro of heading a global drug cartel.

The two individuals taken into custody on Friday are the first to have survived such US attacks.

Sitting alongside Secretary of State Marco Rubio for talks with Ukrainian President Volodymyr Zelenskyy in Washington on Friday, Trump said the strike had targeted, "a drug-carrying submarine built specifically for the transportation of massive amounts of drugs."

Reuters cited sources familiar with the situation Friday as saying the Navy deployed helicopters to rescue the two survivors.

What are the US 'narco' boats' attacks about?

Thursday's attack is believed to be the sixth US attack on "narco" boats off the coast of Venezuela — with the Trump administration claiming to have liquidated 28 individuals in its effort and causing experts to question the legality of such extrajudicial killings, even if the individuals targeted are who the administration claims.

Neither the White House, State Department nor Pentagon have provided evidence in support of the US accusations.

The US has undertaken a sizable redeployment of military hardware to the Caribbean — including stealth bombers and fighter jets — as Trump continues to escalate tensions with Venezuela.

The president also acknowledged this week that he has authorized covert CIA operations inside Venezuela — with Caracas accusing the US of seeking a "regime change."

Asked by a White House reporter on Friday if it was true that Maduro had made overtures designed to ease tensions, Trump said, "He has offered everything, you're right."

When asked on live TV why, Trump retorted, "You know why? Because he doesn't want to f— around with the United States."

Venezuela this week urged the UN Security Council to weigh in on the legality of recent US actions and to reaffirm its backing of Venezuelan sovereignty. 

Edited by: Rana Taha