There was a heavy police presence early Saturday afternoon at the Central Islip train station, where at least one officer could be seen with a gun drawn.
The officer was crouched behind stairs that lead to a pedestrian overpass over the tracks. Suffolk Avenue was blocked while police surrounded the station.
Officers ultimately took a man away in stretcher. It was not immediately known if he was injured.
Suffolk County police could not immediately be reached for comment.
The incident came at a time when the trains were not running. Buses replaced trains between Ronkonkoma and Brentwood all day on Saturday because of track work.