(Photo : Theodore Parisienne/New York Daily News/Tribune News Service via Getty Images)

An ex-con, who had become the poster child for prison reform and was an advocate for counseling at-risk youth, was arrested on second degree murder charges for allegedly shooting a man, and storing his dismembered remains in his freezer and a plastic bin, according to the New York City Department of Corrections. 

Sheldon Johnson, Jr. was put into cuffs after a headless human torso and foot were allegedly found in the freezer of his apartment, located in the High Bridge section of the Bronx. 

He is accused of shooting Collin Small in the head and then dismembering his body. He is charged with murder, manslaughter, weapon possession, criminal contempt, and concealment of a human corpse, per NBC News

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Investigators reportedly found the 44-year-old victim's head, legs, and arms in Johnson's freezer in a secondary apartment located in Harlem. His relationship to the victim remains unknown, but Fox News called Small his suspected killer's "rival." Once in police custody, Johnson, 48, was seen yelling, "I'm innocent!," to reporters.

Johnson acknowledged the cycle of violence that continued to fester throughout his family lineage and isn't the first in his family accused of shocking attacks. 

According to the news outlet, his son — also named Sheldon Johnson – brutally attacked a Columbia University grad student Mingui Yu in Morningside Heights in 2008. He reportedly punched him in the face repeatedly before the victim stumbled into traffic and was slain by a passing SUV. He was charged with manslaughter. 

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(Photo: Theodore Parisienne for New York Daily News/Tribune News Service via Getty Images)

After Johnson's father, Sheldon Johnson Sr. had abandoned his family, he was reportedly arrested in 1986 for raping his 7-year-old stepdaughter three times. 

"Generation to generation, it all stems from me," Johnson Sr. told Buzzfeed in 2016. "I feel disappointed. I regret a lot of the decisions I made in life. It enters my mind all the time. A big, huge amount of guilt. I ruined everything," he said per sign language interpretation. 

Johnson Jr. created programs encouraging amicable interaction between inmates while incarcerated. He also helped to identify dyslexia in prisoners, studied for his bachelor's degree, and gained his certification as a paralegal, which he utilized to provide legal aid to inmates, according to his Formerly Incarcerated Citizens Against Recidivism's bio.

He was featured on "The Joe Rogan Experience" where he spoke with Rogan, 56, about his background, being sentenced, and his experience while in prison. 

"There was never no pre-sentencing investigation. There was never no mitigating evidence presented on my behalf to highlight why I may have made some of the decisions that I made," he began. "He [the judge] just called me a 'menace to society,' and he just gave me 50 years," Johnson said in the Feb. 1 episode.  

Civil rights attorney Josh Dubin, who joined Johnson on the podcast, called him "a miracle."  

Records show Johnson is due to appear in court regarding charges on Monday.