The incident happened onboard a southbound 1 train at 96 Street and Broadway at 3:30 a.m.
The victim was struck in the head with his own cane while riding the subway, according to police.
According to investigators, he had observed the suspect in conflict with another straphanger before he was assaulted.
The suspect then got off the train and fled out of the train station.
The victim is listed in stable condition at the hospital with bruising and abrasions to his head.
Nothing was taken from the victim.
A description of the suspect was not immediately available.
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