Manhattan jurors serving on the trial of a pair of Proud Boys charged for a brawl with violent anti-fascist protesters outside a Republican club will not hear from the alleged victims, prosecutors revealed Thursday.

Assistant DA Joshua Steinglass said that the suspected Antifa members that defendants John Kinsman and Maxwell Hare pummeled, kicked and stomped Oct. 12, 2018, refused to cooperate with the police.

Prosecutors weren’t able to identify the alleged victims after extensive efforts, including social media searches and the use of facial recognition software, Steinglass told jurors during opening statements in Manhattan Supreme Court.

In the indictment, they’re named only as “Spiky Belt,” “Ponytail,” “Shaved Head” and “Khaki” in reference to their appearance in the caught-on-camera melee.

Steinglass said the defendants brutally beat the leftist protesters and “it looked like those injuries had to be significant and possibly disfiguring,” but prosecutors could only charge them with attempted gang assault, attempted assault and riot due to the lack of cooperation.

The violent confrontation unfolded after Proud Boys founder Gavin McInnes delivered a speech at the Metropolitan Republican Club on E. 83rd St. as a hoard of counter-protesters demonstrated outside. To prevent a clash, police directed the attendees to exit west on 83rd then south down Park Avenue.

As Kinsman, Hare and approximately 30 other Proud Boys strolled down Park Avenue, a group of six suspected Antifa members, wearing the movements distinct black masks and clothing, walked toward them then tossed a water bottle at them.

Steinglass told jurors that a gang of Proud Boys charged at the group before the bottle was thrown.

Hare was the first to throw a punch, slugging “Ponytail” and knocking him to the ground. He then allegedly punched, kicked and stomped on “Shaved Head.”

Kinsman allegedly body slammed, kicked and stomped on “Spiky Belt.” Police arrived and the crowd dispersed.

Afterwards, the Proud Boys were “pumped up” about the fight, Steinglass said. “Defendant Hare boasts on video, ‘I f—king hit him. That’s right.’ That same voice continues to brag about how, ‘I kicked him right in the f—king head.’ ”

Defense lawyers for Kinsman and Hare argued that the suspected Antifa members were the aggressors, who started their violent campaign early that morning when the group tossed two bricks into the Republican club building to protest McInnes’ speech.

They also spray-painted their insignia on the club and left a manifesto behind advocating violence. That night, it was the suspected Antifa members, who intentionally circled around the block to confront the Proud Boys, the lawyers argued.

“They’re wearing masks, very intimidating, it’s not Halloween,” said Hare’s attorney, Ronald Hart. “Some of them were wearing plastic knuckles.”

The video of the brawl went viral and the Proud Boys involved in the clash surrendered. McInnes stepped down as the group’s leader.

A total of 10 Proud Boys were charged, seven of whom took plea deals. An eighth is still awaiting trial.