The attack is the latest in a string of killings by the United States that rights groups say are ‘unlawful’.

The United States military says it has attacked a new vessel in the Eastern Pacific, killing three people it accuses of “narco-trafficking”.

The attack announced on Wednesday is the latest in dozens of such strikes carried out by the US military in recent months, a pattern rights groups have slammed as “extrajudicial killings”.

US Southern Command said the latest vessel targeted was operated by unnamed “Designated Terrorist Organizations” who were “transiting along known narco-trafficking routes” in the region.

It shared a video of an air strike appearing to tear into the vessel, which burst into flames.

The US military said none of its forces was harmed in the operation.

The attack comes a day after the US military said another of its strikes ⁠in the eastern Pacific killed four ⁠people, while a separate strike on Monday in the region had killed two.

In total, US attacks on vessels accused of narco-trafficking have killed at least 178 people since September, when US President Donald Trump ordered the attacks to stop what the White House claims are Latin American cartels transporting drugs to the US.

‘US cannot summarily kill people’

Experts and human rights advocates, both in the US and globally, have questioned the legality of the strikes, some of which they say have targeted civilian fishing boats.

Human Rights Watch has ‌said the strikes amount to “unlawful extrajudicial killings”, while the American Civil Liberties Union has cast the assertions by ‌the ‌Trump administration against those it targets as “unsubstantiated, fear-mongering claims”.

Legal experts have said that if some vessels were involved in drug trafficking, those on board should face the law, rather than deadly attacks.

“US officials cannot summarily kill people they accuse of smuggling drugs,” said Sarah Yager, Washington director at Human Rights Watch.

“The problem of narcotics entering the United States is not an armed conflict, and US officials cannot circumvent their human rights obligations by pretending otherwise.”

Critics have also questioned the effectiveness of the US military operation in part because the fentanyl behind many fatal overdoses in the US, which Trump has used to justify his campaign, is typically trafficked to the US over land from Mexico, where it is produced with chemicals imported from China and India.