Police said a suspect is in custody and considered emotionally unstable.
A man first assaulted the father of a child being pushed in a stroller. The father was stabbed in the chest with scissors, and the child was slashed as well, authorities said, adding three other people were stabbed before police descended on the crowded park on the Upper West Side of Manhattan.
"I basically just saw a woman crying," sanitation worker Shurrita Fields told WNBC-TV, New York. "She was bleeding from the neck."
A man suffering a chest wound was taken to Manhattan's St. Luke's-Roosevelt Hospital in serious condition, the New York Fire Department said.
Four others, including the child, were hospitalized at Roosevelt Hospital but expected to survive, authorities said.
The suspect was taken to Bellevue Hospital for evaluation. It was unclear if he was injured, The New York Times reported.
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