It happened just before 9 a.m. on East 88th Street between York and East End Avenue, just down the street from the entrance of Gracie Mansion.
1 dead, 1 critical in Upper East Side shooting
People were out enjoying the day, many with baby strollers, and they ran for cover when the shots rang out.
The NYPD's Chief of Detectives Joseph Kenny said that a custody dispute was the cause of the tragic murder-suicide.
Marissa Galloway, 45, had just placed her child in the car and was putting a stroller in the trunk when the grandmother of the child approached.
Police say that's when 65-year-old Kathleen Leigh took out a 9mm Glock and shot Galloway in the head, and then again in the back as she lay in the street at the back of the vehicle.
Leigh, of Chicago, then shot herself in the head on the sidewalk. She was pronounced dead at the scene.
Galloway was rushed to the hospital where she later died.
There had been an ongoing custody dispute between Galloway and the child's father, who was not injured in the shooting.
The NYPD had records of at least five reports of domestic disputes within the family, as well as two other complaint reports.
Kenny said that the 9mm gun was found on the sidewalk next to Leigh and that another gun was found in her tote bag.
"She is a retired Cook County probation officer living in New York City with family members for the past three years," Kenny said.
Galloway was an experienced runner and longtime track coach at Fordham University.
The university said the community is "deeply saddened by the tragic death.... We keep Marissa and her loved ones in our thoughts and prayers."
She was a Fordham alumna who served as a volunteer assistant track and field coach at Fordham for 17 years until 2019.
Galloway also worked as a teacher in Westchester.
In addition to her 4-year-old, Galloway had a 1-year-old daughter, who is unrelated to the suspect. She was not at the scene.
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