Updated

A teenager was arrested Thursday for the unprovoked stabbing death of New York City poet and activist Ryan Carson in front of his terrified girlfriend after the couple left a wedding on Long Island, police said.

Brian Dowling, 18, is allegedly captured on surveillance footage randomly targeting Carson, 32, and his girlfriend, Claudia Morales.

Dowling, who was spotted in a police cruiser crying, is charged with one count each of murder and criminal possession of a weapon.

After the arrest, the victim's father, Ken Carson, wrote on Facebook, "Assailant has been caught."

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Perp walk

Brian Dowling is accused of stabbing and killing 32-year-old Ryan Carson in Brooklyn, New York, on Monday. (Gregory P. Mango/Pool)

Carson and Morales were sitting on a bus stop bench at the corner of Lafayette Avenue and Malcolm X Boulevard in Brooklyn chatting a little before 4 a.m. Monday when Dowling allegedly strolled by them and started kicking over a row of scooters.

The footage shows the couple starting to walk in the direction of the suspect, who turns around and yells, "What the f--- are you looking at?"

Carson can be heard softly replying that he was not looking at anything, as he steps between the crazed stranger and his girlfriend.

"I'll kill you!" Dowling seethes, as Carson holds up his hand and says, "Chill! Chill!" The unhinged man pulls a knife and pursues Carson, who tumbles over the bench he had just been sitting on. He stabs Carson three times.

The knife-wielding madman rushes at Morales, spits on her then turns back to Carson and kicks him as he lies curled up on the sidewalk. The suspect's girlfriend suddenly appears in the frame and says, "I'm so sorry." 

Morales kneels next to Carson as she calls 911. 

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Brooklyn man and woman pose in photo at wedding.

Ryan Carson, 32, was stabbed to death Monday in Brooklyn in a random attack hours after he and his girlfriend attended a wedding. (X/New York Post )

Morales later told police that the suspect tossed the knife on a pile of trash and then retrieved it before fleeing, according to sources. 

Carson was rushed to Kings County Hospital, where he was declared dead at 4:18 a.m. 

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NYPD Chief of Detectives Joseph Kenny told reporters Wednesday at a press conference on city crime stats that they had identified the suspect but did not release his name. 

"The knife pierces Mr. Carson's heart, causing his death," Kenny said. "As Mr. Carson lay dying on the sidewalk, the male with the knife kicks him in the chest, threatens to stab the woman companion and spits in her face." 

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On Wednesday, Mayor Eric Adams shared his condolences on X, formerly known as Twitter. "Ryan Carson turned his passion into purpose," the mayor wrote. "He advocated tirelessly for others, and his giving spirit was a buoy to all. His murder is unthinkable…I'm praying for all who knew and loved Ryan." 

Sen. Majority Leader Chuck Schumer, D-N.Y., with whom Carson had worked on the Inflation Reduction Act, also offered a tribute on social media.

The beloved community activist moved to New York City from Boston in 2010 to attend Pratt Institute in Brooklyn.

Man in plaid shirt next to wanted poster

Ryan Carson, left, was stabbed to death Monday in an unprovoked attack in New York City. An unofficial Wanted Poster of Brian Dowling before he was caught is shown, right. (Facebook)

Most recently, Carson worked as a senior solid waste campaign manager at the New York Public Interest Research Group, according to his LinkedIn. 

Prior to that, he worked as the executive director of NO OD NY, which he founded to come up with policy solutions to address the crisis of overdose deaths.

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A police source said Dowling had worked at a local high school in Clinton Hill, but a spokesperson for the city's Department of Education said he was not an employee.

Anyone with information is urged to call CrimeStoppers at 800 577 TIPS.