The medical examiner's office determined Williams had been shot in the head and her death was ruled a homicide.
Chad Irish faces a slew of charges, including concealment of a corpse, criminal possession of a weapon and menacing.
Police say Irish threatened a 47-year-old man who identified him at the Strauss Houses on East 28th Street, where Williams' body was found.
Detectives are still looking for a murder weapon and are executing a search warrant in Irish's apartment, where they believe Williams was killed.
Williams stayed with Irish from time to time, but the nature of their relationship is still unclear.
Irish is described as "ambulatory," able to walk around and certainly able to commit a murder. He chooses to use a wheelchair to get around.
Irish has 21 prior arrests in a record that goes back to the early '90s and has been in and out of state prison.
He was most recently released on parole for a July 2022 robbery in the Bronx.
Irish has not been charged with the death of Williams, but the investigation continues.
The community where the woman was found is outraged. On Monday evening, a crowd mobbed Irish as he was taken out of his home on a stretcher and taken into custody. They yelled murderer, cursed him out and threw punches and asked why he would kill a woman who grew up in the neighborhood and who by all accounts never had a problem with anyone.
"Enough people around here were saying that they knew exactly who did it," said neighbor Ted Oehmke. "I think that they probably already didn't like him before and seeing that he did that to this girl, they are understandably enraged and I don't blame them."
Detectives believe Irish was the man in the motorized wheelchair seen on video dragging and leaving the body on East 27th street Friday, using a dolly to wheel it.
Meanwhile, family and friends continue to mourn the death of their loved one as a makeshift memorial has been created.
Williams' family described her as someone who wanted to be an advocate for women and part of the justice system to fight for victims.
"She was beautiful, she was sweet, she was college-educated, she was just a good person," said the victim's aunt Nisha Ramirez.
Senator Kristen Gonzalez, Assemblymember Harvey Epstein and Councilmember Carlina Rivera released a joint statement on Williams' death and said they also are grieving and outraged:
"Our hearts go out to Yazmeen's family, particularly her mother, Nicole Williams, who has shown immense strength during this unimaginably difficult time. Yazmeen was a bright and accomplished individual, a graduate of Buffalo State University with a degree in criminal justice, and she had just begun a promising career with the New York City Housing Authority. The loss of someone so deeply committed to the wellbeing of her neighbors is immeasurable. This tragedy has left a void in the hearts of all those who knew and loved her."
The statement went on to say that members of the Straus Houses community have requested more security cameras to enhance safety and the lawmakers will do everything in their power to improve safety and security.
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