The U.N. human rights chief has urged the United States to examine whether its recent attacks on suspected drug-smuggling vessels were lawful, citing "strong indications” that the operations amounted to extrajudicial killings.

The United States has carried out a series of strikes in the Caribbean and the Pacific in recent weeks on boats that Washington claims were ferrying drugs, killing a total of 76 people.

Six of them were killed this past weekend, with U.S. Defense Secretary Pete Hegseth saying on X on Monday that the U.S. military had conducted strikes in international waters in the eastern Pacific, targeting two boats "carrying narcotics" with three people on board each.

"From what we know, these instances violate international human rights law," United Nations High Commissioner for Human Rights Volker Turk told AFP in an interview.

Pointing out that Washington was portraying the strikes as part of "counter-narcotics operations", he stressed that such operations "should not bring in issues of war or conflict or international humanitarian law".

These should be considered "law enforcement operations", which fall under international human rights law, he said, insisting that in such cases, "the use of lethal force has to be extremely limited".

"It has to be the absolute last resort in the face of an immediate attack," he said, stressing that "that's not what we're seeing".

Asked if he believed that the strikes could constitute extrajudicial killings, Turk said: "That's precisely what needs to be found out and investigated."

"I have called for investigations by the U.S. administration first and foremost, because they need to... ask themselves the question: are these violations of international human rights law? Are they extrajudicial killings?"

"There are strong indications that they are, but they need to investigate this."