NEW YORK -- A suspect has been charged for the stabbing death of beloved Brooklyn activist Ryan Carson, police sources told ABC News.
Brian Dowling has been arrested on charges of murder with depraved indifference and criminal possession of a weapon.
He is expected in court on Thursday.
According to police sources, detectives were searching Dowling's home when he showed up.
At the home, detectives recovered the sweatshirt he appears to have been wearing in surveillance images of the stabbing, along with a knife that will now be tested to see if it matches the murder weapon.
Carson, 31, was stabbed to death while waiting for the bus with his girlfriend, in what appeared to be a random, unprovoked attack.
Officials say Carson put himself between his stabber and his girlfriend before the fatal attack.
NYPD Chief of Detectives Joseph Kenny said there were no prior interactions between Carson and his girlfriend and the suspect.
Video shows the couple trailing behind the suspect who suddenly kicks mopeds and bikes and asks Carson what he is looking at. Police say the video shows the suspect pulling out a knife and as Carson backed up to get away, he stumbled over a bench. While on the ground, video shows the suspect stab the victim.
Despite the break in the case, friends and family are left shattered as they remember Carson's unwavering passion for change.
"It's incredibly tragic," said Blair Horner, Carson's former boss at the New York Public Interest Research Group, who shared he was passionate about his work. "A life full of promise is snuffed out. And the world is a worse place for it, and we'll miss him dearly."
He is remembered for his selfless acts and outgoing personality.
"I met Ryan when I was 19 and we were both students at Pratt Institute studying writing. Ryan and I actually became close friends because I was experiencing a time in my life where I had nowhere to live and not enough money to eat everyday, to be perfectly frank. Ryan offered me up a space to live, he barely knew me by many measures, and he really helped me through that difficult summer and helped me get back on my feet," friend Hannah Holden said. "That was how our friendship began, and that's the kind of person he was. He was so incredibly generous. He was so supportive of people. He was an amazing person."
Carson touched many people's lives and poured himself into everything he did. He was passionate about a grassroots effort he started after his best friend died of a heroin overdose in 2016.
Through No OD NY, he hoped to create overdose prevention centers all over the state, which was just one example of his desire to change the world and make it a better place.
"He wanted to channel his grief into something that was productive and something that was going to help others," Holden said.
VIDEO | Remembering the life and legacy of a beloved Brooklyn activist: