U.S. Defense Secretary Pete Hegseth is seen at the Oval Office of the White House, in Washington, D.C., U.S., August 18, 2025. REUTERS/Kevin Lamarque/File Photo

By Idrees Ali, Phil Stewart and Jeff Mason

WASHINGTON (Reuters) -U.S. Defense Secretary Pete Hegseth said on Wednesday that military operations against cartels would continue, setting the stage for a sustained military campaign in Latin America even as basic questions about a deadly strike against a vessel from Venezuela remained unanswered.

The U.S. military killed 11 people on Tuesday in a strike on a vessel from Venezuela allegedly carrying illegal narcotics, in the first known operation since President Donald Trump's recent deployment of warships to the southern Caribbean.

Little is known about the strike, including what legal justification was used or what drugs were on board, but Hegseth said operations would continue.

"We've got assets in the air, assets in the water, assets on ships, because this is a deadly serious mission for us, and it won't stop with just this strike," Hegseth said on Fox News.

"Anyone else trafficking in those waters who we know is a designated narco terrorist will face the same fate," Hegseth said.

He declined to provide details on how the operation was carried out, saying they were classified. It is unknown whether the vessel was destroyed using a drone, torpedo, or by some other means.

After the strike, Trump said on Tuesday the U.S. military had identified the crew as members of Venezuelan gang Tren de Aragua, which the United States designated a terrorist group in February.

On Wednesday, Trump told reporters in the Oval Office that "massive amounts of drugs" were found on the boat, but did not specify the type of drugs or the quantity.

"We have tapes of them speaking. It was massive amounts of drugs coming into our country to kill a lot of people. And everybody fully understands that. In fact you see it, you see the bags of drugs all over the boat," Trump said.

"Obviously they won't be doing it again. And I think a lot of other people won't be doing it again. When they watch that tape, they're going to say, 'Let's not do this.'"

The Pentagon has not released specifics about the crew and why it chose to kill those on board.

Presidents of both major U.S. parties have in the past, asserted the authority to use the military for limited strikes when there is a threat to the United States, as Trump did in June when he ordered an attack on Iran.

But it is unclear what legal authority Trump used in this case.

Mary Ellen O’Connell, an expert on international law and the use of force with the University of Notre Dame, said Tuesday's operation "violated fundamental principles of international law."

"The alleged fact that the attack was on the high seas is irrelevant. What is relevant is that the U.S. had no right to intentionally kill these suspects," she said.

MADURO 'SHOULD BE WORRIED'

The decision to blow up a suspected drug vessel passing through the Caribbean, instead of seizing the vessel and apprehending its crew, is highly unusual and evokes memories of the U.S. fight against militant groups such as al Qaeda.

The United States has deployed warships in the southern Caribbean in recent weeks, with the aim of following through on a pledge by Trump to crack down on drug cartels.

Seven U.S. warships, along with one nuclear-powered fast attack submarine, are either in the region or expected to be there soon, carrying more than 4,500 sailors and Marines.

U.S. Marines and sailors from the 22nd Marine Expeditionary Unit have been carrying out amphibious training and flight operations in southern Puerto Rico.

Asked about Venezuela's close relationship with China, Hegseth took aim at Venezuelan President Nicolas Maduro.

"The only person that should be worried is Nicolas Maduro, who is ... effectively a kingpin of a drug narco state," Hegseth said.

Trump said Venezuela had been a "very bad actor."

U.N. spokesperson Stephane Dujarric said on Wednesday Secretary-General Antonio Guterres remains very concerned about heightened tensions between the U.S. and Venezuela.

The Trump administration last month doubled the reward for information leading to the arrest of Maduro to $50 million, accusing him of links to drug trafficking and criminal groups.

Venezuelan officials have said the Caribbean buildup is meant to justify an intervention against them, with Maduro accusing Trump of seeking "regime change."

Authorities in the South American country, who say Tren de Aragua is no longer active there after being dismantled during a prison raid in 2023, suggested on Tuesday that footage shared by Trump of a speedboat at sea exploding and then burning was created with artificial intelligence.

Reuters conducted initial checks on the video, including a review of its visual elements using a manipulation detection tool that did not show evidence of manipulation. However, thorough verification is an ongoing process, and Reuters will continue to review the footage as more information becomes available.

The strike drew skepticism from some within the Venezuelan opposition.

"How did they know there were 11 people? Did they count them? How did they know they were Venezuelan? Were their ID cards floating on the sea afterward?" former opposition presidential candidate Henrique Capriles told Reuters.

Capriles recently returned to the National Assembly as a lawmaker, though the country's main opposition faction, led by Maria Corina Machado, boycotted the 2025 legislative election.

Machado has been supportive of Trump's previous moves against Maduro.

(Reporting by Idrees Ali, Phil Stewart, Susan Heavey and Jeff Mason; Additional reporting by Michelle Nichols and Tom Hals; Editing by Ros Russell, Mark Porter, Rod Nickel)