During the dispute, the woman tried to pass her 1-year-old baby to her mother and she dropped the baby. At that time the man began to spray pepper spray at the woman and the 1-year-old.
EMS responded to the scene and transported the mother and baby, who were both hit with pepper spray to Lutheran Hospital in Sunset Park at 8 p.m. on Thursday.
They are expected to be okay.
The man was arrested at the scene by a transit officer and is in custody.
There is no information being released on charges.
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