The NYPD is investigating the department's response to the fatal stabbing of Lesandro Guzman-Feliz last week.
Video shows the teen collapsing in front of Saint Barnabas Hospital after being stabbed about a block away.
The new video reportedly shows officers at the hospital standing by as the teen bleeds to death.
Guzman-Feliz's death has brought nationwide reactions and calls to end gang violence.
The NYPD is reviewing the video.