Rodrigo Duterte, the former president of the Philippines, has appeared at the International Criminal Court, accused of crimes against humanity.
The 79-year-old appeared in the Netherlands via video link on Friday.
His lawyer said he was suffering from "debilitating medical issues" but the judge in The Hague, Iulia Motoc, said the court doctor had found him to be "fully mentally aware and fit", adding that he was allowed to appear remotely because he had taken a long flight.
The lawyer, Salvador Medialdea, also claimed Duterte's arrest and transfer were "pure and simple kidnapping".
Wearing a jacket and tie, Duterte sounded frail as he spoke briefly to confirm his name and date of birth.
He was read his rights and informed of the charges. His supporters contest his arrest and say the court does not have jurisdiction.
If convicted, he faces life in prison.
His daughter Sara Duterte, the current vice president of the Philippines, said she was hoping to visit her father and have the hearing moved after meeting supporters outside the court.
Back home in the Philippine capital region, large screens were set up to allow families of suspects killed in brutal crackdowns on illegal drugs to watch the proceedings.
Prosecutors accuse Duterte of forming and arming death squads said to have killed thousands of drug dealers and users during the crackdowns.
Estimates of the death toll during his six-year presidential term vary, from more than 6,000 reported by national police, to 30,000 claimed by human rights groups.
Prosecutors claim he was an "indirect co-perpetrator" in multiple murders, allegedly overseeing killings between November 2011 and March 2019.
Before becoming president, Duterte was the mayor of the southern city of Davao.
According to the prosecution, he issued orders to police and other "hitmen" who formed the so-called "Davao Death Squads" or DDS.
The warrant for his arrest said there were "reasonable grounds to believe that Mr Duterte bears criminal responsibility for the crime against humanity of murder".
Duterte has said he takes full responsibility for the "war on drugs".
Following the initial hearing, a confirmation of charges hearing is likely to follow. That is when prosecutors present part of their evidence and judges decide which charges can be in an indictment.
A trial is unlikely to begin before early 2026.
Duterte was arrested on Tuesday amid chaotic scenes in Manila, the capital of the Philippines, after returning from a visit to Hong Kong.
He told officers "you have to kill me to bring me to The Hague" during a 12-hour standoff, a Philippine police general said.
He also refused to have his fingerprints taken and threatened Police Major General Nicolas Torre with lawsuits before he was bundled onto a government-chartered jet at a Philippine air base and taken to The Hague, Maj Gen Torre told the Associated Press.
(c) Sky News 2025: Former president of Philippines Rodrigo Duterte appears in court accused of running death squads