NEED TO KNOW

  • Prosecutors have released additional details into the Massachusetts woman who was arrested after allegedly stabbing a tourist at Macy’s flagship store in New York City on Dec. 11
  • They said she was hospitalized for psychiatric problems and was released after a year-long stay at a Manhattan psychiatric ward on the morning of Dec. 11
  • She previously was arrested 2018 for posting on Facebook that she wanted to kill Sen. Elizabeth Warren, prosecutors said

The woman who was arrested after allegedly stabbing a tourist at Macy’s flagship store in New York City reportedly had a history of mental illness. 

Kerri Aherne — the 43-year-old woman who is facing charges including attempted murder and assault in connection with the incident — made her first court appearance on Friday, Dec. 12, where it was determined that she would be held without bail, according to WABC, Fox News and the New York Post.

Prosecutors with the Manhattan District Attorney’s Office said during her arraignment, per the outlets, that she had been released after a year-long stay at a Manhattan psychiatric ward on the morning of Dec. 11 — hours before the alleged attack happened — and wandered into the Macy’s flagship store.

“She had purchased a knife at Macy’s and looked for someone to kill because voices in her head told her that she had to kill someone or else she would be killed,” Manhattan Assistant District Attorney Paul Barker told the court, per the New York Post.

Macy’s in New York City.

Sipa via AP Images

Prosecutors said she then entered the Macy’s bathroom on the seventh floor and stabbed the victim — a 39-year-old woman from California — as she was changing her baby, WABC reported. The baby fell from the changing table to the floor, though was not injured in the incident, per the outlet.

Law enforcement officers with the New York Police Department responded to Macy’s Herald Square on Dec. 11 at around 3:15 p.m. local time after a report of an assault, the NYPD confirmed in a statement to PEOPLE.

Police said the woman — who was later identified by the NYP as an employee for the Los Angeles County Sheriff’s Department — sustained “multiple stab wounds to her back and a laceration to her left arm.” She was transported to the hospital and was discharged on Friday.

The injured woman’s husband told the NYP that she “is better,” following the incident.

Aherne was charged with attempted murder, two counts of assault, criminal possession of a weapon and endangering the welfare of a child, the NYPD said.

Prosecutors said in a criminal complaint, per WABC and Fox News that Aherne, who is from Massachusetts, told police that she had been hospitalized for psychiatric problems. The 43-year-old was arrested in 2018 in her home state for posting on Facebook that she wanted to kill Sen. Elizabeth Warren, prosecutors said, per the outlets. 

The following year, she was deemed an incapacitated person and her mother and sister were appointed as her guardians and she was placed on a court-ordered treatment plan to take  medication used to treat schizophrenia, according to the NYP.

The Macy’s storefront is decorated for Christmas in Herald Square on Dec. 11, 2025.

ANGELA WEISS / AFP via Getty

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According to the bail application obtained by the outlets, Aherne left Massachusetts in an Uber in the summer of 2024 while out of the hospital on temporary leave, and allegedly said she could not tolerate hospitals any longer and would rather be in prison.

In court, she echoed similar sentiments saying, per the NYP, “I don’t want to go to another hospital. They didn’t help me at Manhattan Psychiatric Center.”

Aherne’s next appearance in court is scheduled for Dec. 17.

If you or someone you know needs mental health help, text “STRENGTH” to the Crisis Text Line at 741-741 to be connected to a certified crisis counselor.