The United States military has carried out more lethal strikes on alleged drug traffickers, as part of a campaign that some legal experts say goes against international law and is akin to murder.
A series of strikes on suspected drug vessels in the eastern Pacific killed 14 alleged drug traffickers and left one survivor on Tuesday, according to US officials.
The strikes followed at least 10 others in the Caribbean and Pacific since early September, which have resulted in at least 46 deaths.
The crackdown is part of US President Donald Trump's anti-drug campaign and raises questions around how international law applies when a nation kills untried people in foreign territory.
How has the US justified its actions?
US defence secretary Pete Hegseth has attempted to justify the strikes on alleged drug traffickers, saying intelligence agencies have identified these boats as involved in "illicit narcotics smuggling".
"Narco-terrorists intending to bring poison to our shores will find no safe harbour anywhere in our hemisphere," Hegseth said after a previous boat was targeted earlier this month.
The Pentagon has provided little information, giving few details about the quantity of drugs the boats allegedly carried and the identities of those killed.
The Trump administration says it has classified legal opinion that it says authorises lethal strikes against a secret and expansive list of cartels and suspected drug traffickers.
CNN reported earlier this month that the opinion "argues that the president is allowed to authorise deadly force against a broad range of cartels because they pose an imminent threat to Americans".
Donald Rothwell, a professor of international law at the Australian National University, told SBS News the legal opinion was developed by the Trump administration to justify the military strikes.
Rothwell said this is "on the grounds that the US is engaged in a non-international armed conflict and as such the persons on board these boats are combatants and legitimate targets".
He said: "There is little evidence to suggest that whatever criminal enterprise those on board these boats are engaged in amounts to an armed conflict."
Sarah Joseph, a professor of law at Griffith University, told SBS News the classified legal opinion likely relates to US law, rather than international law.
She said the US tends to "care more about the former than the latter"; however, a legal opinion in and of itself does not "magically transform the illegal into the legal".
"There is no basis for an argument that this action complies with international law, and no state can unilaterally change that with their own legal opinion," Joseph said.
"One might, for example, recall the infamous torture memos under the Bush Jr administration."
The 'torture memos' were a series of legal documents created by the US government that said using enhanced interrogation techniques, such as waterboarding, on detainees it held overseas was legally permissible. Initially created in 2002 under the presidency of George W Bush, they were later rescinded by then-US president Barack Obama in 2009.
Joseph added that the classified nature of the current document "obviously hampers people in judging its rigour, credibility and bona fides".
Lawyer: Strikes illegal under international law
The US could be seen as attempting to justify the killings under its own domestic laws, but this is hard to determine, given that it has classified its reasons.
But under international law, the strikes are illegal, according to Joseph.
"A state cannot kill people, whether their own citizens or other citizens, because they suspect they are carrying drugs to their country," she said.
"This is the same sort of behaviour for which former Philippines president [Rodrigo] Duterte has been indicted before the International Criminal Court."
Joseph said the US has obligations under international human rights law regarding the right to life, which it is breaching.
She explained this can be seen as an "extraterritorial breach" when a state's actions outside of its own territory cause harm to others. These violations can involve activities like armed conflicts, detentions, or environmental harm that cross international borders.
The US has regularly disputed this idea that international human rights laws have extraterritorial application, Joseph added.
"However, it is very much in the minority among States on that issue; I believe extraterritorial application is well-established and no longer arguable," she said,
Law of the sea
The law of the sea is an international body of law that regulates activities in the oceans and seas.
This includes maritime boundaries, shipping, fishing, and resource management.
Rothwell said there is no legal basis under the law of the sea for these US strikes on alleged drug boats.
"These waters are ones in which high seas freedoms of navigation apply," he said.
"Historically, only pirate ships can be stopped on the high seas and even then, they cannot be targeted with a military strike."
Australia is a "persistent supporter" of the law of the sea, he said, and is a party to the 1982 UN Convention on the Law of the Sea, a document which codifies legal principles.
Strikes have potential to be crimes against humanity
Joseph said the targeted killings could even constitute crimes against humanity.
"International criminal law might apply if the strikes reach the level of a crime against humanity," she said.
"That is what Rodrigo Duterte has been charged with based on extrajudicial killings in a local 'war on drugs'".
While a single murder is "very unlikely" to be classified as a crime against humanity, Joseph said that as the strikes continue and increase, the argument that they constitute crimes against humanity becomes stronger.
Does Australia have a responsibility to condemn the strikes?
Joseph said that the international community, including Australia, should be critical of the strikes.
"These are significant breaches of international law. The US is murdering people on the high seas. Australia and all states should therefore condemn the strikes."
Rothwell said that, given Australia's support for the law of the sea, the country should uphold its legal principles, which do not give a basis to justify the lethal strikes.
"Especially in the context of the South China Sea, Australia should be making clear its position on this US conduct."
