WASHINGTON - The US military struck a vessel conducting narco-trafficking in international waters just off the coast of Venezuela on Tuesday, killing six men aboard, US President Donald Trump said on Truth Social.

The latest operation raised the death toll to 27 in a series of US military strikes against suspected drug trafficking vessels near Venezuela since September.

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According to Trump, US intelligence confirmed the vessel was transiting along a known route and associated with illicit narco-terrorist networks.

Earlier this month, the Trump administration notified Congress in a memo that the United States is in a "non-international armed conflict" with drug cartels it has designated as terrorist organizations and will treat their members as "unlawful combatants."

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The memo did not specify the names of the cartels or disclose the standards the US government would use to decide whether someone is sufficiently connected to a cartel to warrant targeting.

Venezuelan President Nicolas Maduro has repeatedly accused the United States of invoking cartel threats as a pretext for pursuing regime change and expanding its military presence in Latin America.