BROOKLYN, NEW YORK: An 18-year-old person of interest in the harrowing random stabbing death of a beloved Brooklyn social justice activist was apprehended on Thursday morning, October 5, after authorities recovered a knife and the sweatshirt the accused is said to have worn at the time of early morning murder.

The perpetrator, who has been named Brian Dowling, was arrested when NYPD officers executed a search warrant at a home on Lafayette Avenue near Malcolm X Boulevard, just a few blocks away from where Ryan Carson, 32, was knifed to death on early Monday, October 2, as his girlfriend watched.

Brian Dowling is said to be 'mentally disturbed'

Authorities were trying to find out the clothing reportedly worn by the suspect during the caught-on-camera attack and discovered thta both Dowling and his dark Champion sweatshirt, seen in the video of the attack, inside the apartment.

Police also found a knife in the apartment and will be working to determine if it was the murder weapon.

According to Daily Mail, sources close to law enforcement previously identified a “mentally disturbed” teen as the main suspect in the murder of Carson who was attacked near a B38 bus stop in Bedford-Stuyvesant just before 4 am on Monday, October 2.

Ryan Carson and his partner were heading home before the attack

Police said that Carson, a longtime campaign organizer for the New York Public Interest Research Group, and his girlfriend were heading home from a wedding on Long Island when the unfortunate incident took place.

The assailant seemed to target Carson at random, prompting the community advocate to stand between the stranger and his girlfriend, the distressing footage obtained by the outlet showed.

The lunatic can be heard yelling, "I'll kill you" before the two struggled with Carson eventually tumbling over the bus stop bench while the attacker pulls out a knife and stabs him three times.

Carson lay on the ground while the attacker turned on his girlfriend and spat on her. An unknown female individual, who police claim knows the suspect, then appears in the corner of the frame and seems not to “hurt him” and repeats what sounds like “Brian.”

Carson died from a stab wound that pierced his heart, officials said.

Brian Downling's troubled past

During a press conference on Wednesday, October 4, NYPD Chief of Detectives Joseph Kenny said police had identified the alleged perpetrator but were waiting for “probable cause to make this arrest".

Dowling was issued three summons last year, including two for disorderly conduct. He was also cited in an incident report related to a July incident in which his aunt claimed he smashed objects in his girlfriend’s apartment following a fight and described him in a 911 call as "mentally disturbed."

According to police, the alleged attacker may have engaged in a physical altercation with his girlfriend shortly before he began kicking over and damaging mopeds and scooters that were parked on the sidewalk.

Dowling then turned on Carson, seething, “What the f**k are you looking at?”

The teen reportedly works at a high school in Clinton Hill and is known to frequent the area of Commodore Barry Park in Fort Greene.