Police identified the victim as Yaw Boahene, who was getting off the train just before 6 p.m. When his bag snagged in the closing doors. He was pulled backward, then dragged between the train cars and onto the tracks below.

Boahene was pronounced dead at the scene, according to police.

A witness heading home from school saw the whole thing happen. She described it as horrific and said it left her traumatized.

The death raises fresh questions about door safety systems on subway trains and how quickly operators can react when something, or someone, gets caught as cars pull away from a platform. For riders who commute through Utica Avenue every day, the incident is a jarring reminder of how routine, and how dangerous, the simple act of stepping off a train can become in a split second.

Investigators have not said whether a mechanical malfunction played a role or whether the doors closed on schedule as Boahene attempted to exit.

A bag strap. A closing door. A man is dead, and a stranger who happened to be walking home will never forget what she saw.