It began with an altercation between two men on a New York subway platform, but minutes later, one of them was dead after being struck by an oncoming train.

A shocking photo of the victim on the tracks before his death was used on the front page of the New York Post.

R. Umar Abbasi, a Post freelance photographer, captured the images after the man, 58-year-old Ki-Suck Han, witnesses say, was shoved off the platform.

Abbasi claims he was trying to use his camera's flash to try and alert the train's driver to stop. The "Post" nonetheless is coming under a lot of criticism for publishing the photos -- and people are questioning why no one else helped Han off the tracks.

In an interview Tuesday night, HLN's Dr. Drew told CNN'S Anderson Cooper, "[I'm] betting that the probability is there was some bystander effect" -- a situation where an individual is more likely to help than if he was part of a group. "Prepare for a bystander effect. Just because we have that psychological tendency doesn't mean we have to give in to it."

Acknowledging that not all the facts have been released, Dr. Drew added, "I hope it was a helpless situation that people would have loved to have intervened but just simply didn't feel they could."

Continuing the conversation in a broader sense Wednesday night, Cooper told Dr. Drew, “I do think that …the larger issue here [is] people not being citizens, and, instead, just being observers. Reporters have a role as observers, but people should also be citizens and be actively engaged.”

Hear more in the video clip above.

Dr. Drew On Call airs Monday through Wednesday on HLN at 9 p.m. ET.  Follow the show on Facebook and Twitter @DrDrewHLN.

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