A New York City police officer was shot and killed Monday during a traffic stop, the city’s mayor said. It marked the first slaying of an NYPD officer in two years.

“We lost one of our sons today and it is extremely painful. It is extremely painful,” Mayor Eric Adams said, addressing reporters at the hospital where the officer died.

The shooting happened just before 5:50 p.m. in the Far Rockaway section of Queens, police said, after Officer Jonathan Diller and his partner encountered a vehicle illegally parked at a bus stop.

As they approached the vehicle, a man inside shot Diller below his bulletproof vest, said Police Commissioner Edward Caban. Diller’s partner returned fire and wounded the suspected shooter, who was brought to an area hospital.

Diller was taken to Jamaica Hospital Medical Center but could not be saved, officials said. He had been with the police department for three years, was married and had a young child, Caban said on the social media platform X.

“We struggle to find the words to express the tragedy of losing one of our own,” Caban wrote.

The police department’s chief of detectives, Joseph Kenny, said Diller and his partner had initially tried to order the vehicle’s driver and passenger out of the car, which was stopped on a busy but narrow street in a bustling commercial district.

“He was asked to leave the car,” Kenny said of the person who pulled the gun. “He was given a lawful order numerous times to step out of the car. He refused. And when the officers took him out of the car, rather than stepping out of the car, he shot our officer.”

Kenny said Diller “stayed in the fight” after being wounded and tried to disarm the shooter, whose name was not immediately released by police.

“The gun hit the ground. And as the perpetrator was still reaching for it, this cop was able to grab it, although he was still shot,” Kenny said.

Witnesses described a chaotic scene.

“It happened so fast,” one bystander, Melissa Morgan, 39, told the Daily News. “The police officer fell on the floor and the other officers dragged the two guys out of the car. I was running for cover.”

Another witness, Deon Peters, told the New York Post he saw Diller on the ground.

“He was moving, he was saying ‘I’m hit, I’m hit,’” Peters said.

The slaying was the first of an NYPD officer since 2022, when two officers, Wilbert Mora, 27, and Jason Rivera, 22, were ambushed in a Harlem apartment building after responding to a domestic disturbance call.

Adams, a former police captain, said he met with Diller’s grieving widow. He called the shooting a “senseless act of violence.”

“Can I say it any clearer? It is the good guys against the bad guys,” he said. “And these bad guys are violent. They carry guns. And the symbol of our public safety, which is that police uniform, they have a total disregard for.”

One of the people in the vehicle had been arrested on a gun charge in April 2023, Kenny said.

Patrick Hendry, president of the Police Benevolent Association of New York, expressed anger over the shooting.

“These attacks on New York City police officers have to end right now,” he said. “We have a family upstairs that’s devastated. We have police officers in this hallway who lost a brother. It has to end now.”