One of the men convicted in the murder of Lesandro “Junior” Guzman-Feliz has been found dead behind bars. On Friday, Jonaiki Martinez-Estrella, 31, was discovered unresponsive in his cell at Coxsackie Correctional Facility, located in Coxsackie, New York.
According to CBS News, prison staff immediately performed life-saving measures, including CPR, Narcan, and the use of an automated external defibrillator (AED). However, all efforts to revive Martinez-Estrella were unsuccessful. The Greene County Medical Examiner is now working to determine the official cause of death. Martinez-Estrella had been serving a 25-years-to-life sentence for his involvement in Junior’s violent death — a case that sparked nationwide outrage and the viral hashtag #JusticeForJunior.
Martinez-Estrella Was Previously Convicted of First-Degree Murder
The case dates back to June 2018, when 15-year-old Junior Guzman-Feliz was dragged from a Bronx bodega and stabbed multiple times by members of the Trinitarios gang, who reportedly mistook him for a rival gang member. The murder, caught on surveillance footage, shook the community and led to multiple arrests. Martinez-Estrella was identified as the gang member who delivered the fatal blow to Junior with a machete. He was initially convicted of first-degree murder and sentenced to life without parole in October 2019.
But in a surprising twist, the New York State appeals court overturned his conviction in 2023, citing potential procedural issues. That decision set off new proceedings.
Resentenced on Lesser Charges in May
Despite the overturned conviction, prosecutors successfully tried Martinez-Estrella again. In May, he was resentenced to 25 years to life after being found guilty of second-degree murder, conspiracy, and gang assault.
Under this new sentence, Martinez-Estrella was eligible for parole — a major departure from his prior life-without-parole term. Still, he remained incarcerated as part of one of the most notorious gang-related killings in recent New York history.
Justice for Junior: A Bronx Community Still Healing
Junior’s murder became a national symbol of gang violence and systemic failure. His story moved people across the country — from celebrities like Cardi B to everyday Bronx residents. The movement to get justice for Junior led to multiple convictions, increased scrutiny of gang activity, and calls for youth protection and reform.