Guy Rivera is on trial in the death of Officer Jonathan Diller during routine traffic stop in Far Rockaway in March 2024

The suspect accused of gunning down NYPD officer Jonathan Diller appeared to be smiling in police bodycam video just moments after the fatal shooting, according to testimony from one of Diller’s fellow officers.

NYPD Detective Derval Whyte took the witness stand in a Queens courtroom Wednesday, describing how he “watched my friend get sH๏τ for no reason” during a routine traffic stop in March 2024. Whyte went on to recount Diller’s final moments, the New York Post reported.

“He’s on his back, he’s motionless,” he said of Diller. “I heard him say, ‘I’ve been sH๏τ.’ I went over to find the gunsH๏τ wound. I rolled him back and forth and found the bullet wound above his belly.”

Body camera footage played for the court showed the moments officers attempted to revive Diller in the immediate aftermath of the shooting. The footage also showed a man on the ground in handcuffs who appeared to be grinning, the outlet reported.

When he was asked to describe the footage, Whyte said, “That’s the defendant. He looks like he’s smiling.”

Diller, a 31-year-old married father, was inspecting a suspicious vehicle parked outside a T-Mobile store in Far Rockaway on March 25, 2024, when 35-year-old Guy Rivera, who was seated in the pᴀssenger seat, allegedly fired three rounds at the officer, striking him in the stomach.

Rivera, a career criminal with nearly two dozen prior arrests, according to police, pleaded not guilty to first-degree murder charges after prosecutors said he gunned down Diller.

ᴀssistant District Attorney Ken Zawistowski described the fatal encounter during the trial’s opening statements last week.

“[Rivera] took out his gun and pointed it at officer Diller,” Zawistowski said.

“He sH๏τ officer Diller underneath his bulletproof vest, causing his intestines to be ripped through and causing his iliac artery to be severed — one of the body’s most vital arteries,” Zawistowski continued.