Two European eyewitnesses to the altercation that left Jordan Neely dead and New York City Marine infantry veteran Daniel Penny facing manslaughter charges have gone home and refused to cooperate with prosecutors from Manhattan District Attorney Alvin Bragg's office, according to a local report.

Penny, 25, is scheduled to go to trial next month after he appeared on cellphone video placing Neely, 30, in a chokehold as other passengers helped restrain him in May 2023. 

The homeless Neely was threatening subway riders and behaving erratically and had a history of mental illness and violence, including the 2021 assault of a 67-year-old woman. He lost consciousness and later died.

The foreign witnesses have spoken with investigators on conference calls but have declined to cooperate or turn over video of the incident, the New York Post reported, citing transcripts from a closed-door meeting with the judge and attorneys for both sides.

US MARINE VET DANIEL PENNY PLEADS NOT GUILTY TO MANSLAUGHTER IN CHOKEHOLD DEATH OF JORDAN NEELY

Daniel Penny exits court

Daniel Penny departs Manhattan Criminal Court Jan. 17, 2024. Penny is charged in the New York City subway death of Jordan Neely in 2023. (John M. Mantel for Fox News Digital)

Penny's lawyers declined to discuss the proceedings Thursday but were quoted in the transcript saying the European couple's testimony would be "incredibly favorable to the defense."

Representatives for Bragg's office did not immediately respond to requests for comment.

"They have so far refused to share the video that they took," the judge told the lawyers. "They refused to share it with the DA or with anyone else, and they are so far refusing to come back to testify."

DANIEL PENNY: MARINE VET ACCUSED OF FATAL SUBWAY CHOKEHOLD REVEALS WHY HE STEPPED IN

Daniel Penny shown holding Jordan Neely in a chokehold.

A screenshot from a bystander's video showing Jordan Neely being held in a chokehold on the New York City subway. (Luces de Nueva York/Juan Alberto Vazquez via Storyful)

It was unclear Thursday what the European couple's video might show.

Prosecutors said in June 2023 that they had already obtained five eyewitness videos of the encounter and surveillance video they planned to introduce as evidence.

"Unfortunately for Penny’s defense team, there is little they can do to compel a foreign national to turn over evidence or testify in court," said Neama Rahmani, a former federal prosecutor based in Los Angeles. "There are international treaties like the Hague Convention that allow for international service, but, practically speaking, no judge can force the European witnesses to comply with an American subpoena."

Still, he said, self-defense cases are often difficult to prosecute and result in many not guilty verdicts.

"Penny’s lawyers will have to rely on witnesses who have actually provided evidence to law enforcement and prosecutors and who live in the state and can be compelled to testify by the judge even if they don’t want to," he added.

WITNESS TO JORDAN NEELY CHOKEHOLD DEATH CALLS DANIEL PENNY A ‘HERO’

Jordan Neely, left, with Carolyn Neely smiling in a selfie

This undated photo, provided by Mills and Edwards, LLP, in New York, May 12, 2023, shows Jordan Neely, left, with Carolyn Neely, an aunt. (Courtesy Mills & Edwards, LLP via AP)

Critics of Bragg's decision to prosecute Penny have called the move political and believe that the veteran acted in self-defense and to protect other passengers.

"If [Neely] had carried out his threats, he would have killed somebody," Penny told Fox News Digital in June 2023.

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Another witness expressed similar concerns.

"I don’t care if I have to kill an F, I will," Neely had allegedly ranted. "I’ll go to jail, I’ll take a bullet."

Penny, who spoke with police voluntarily 11 days before Bragg's office brought charges, faces up to 19 years in prison if convicted. His next court hearing is scheduled for Oct. 3.