07/31/2013 12:17 EDT

Sammy Yatim Video Shows Leg Spasms, Removal From Streetcar (GRAPHIC)

An upsetting new Sammy Yatim video shows the 18-year-old's final moments after he was shot by police on an empty Toronto streetcar early Saturday morning.

The "first on scene" video was posted to YouTube Saturday, but has only received attention over the last 24 hours. The footage shows the aftermath at the crime scene, with police milling about while CPR is performed on Yatim.

You can hear an officer or paramedic loudly counting as he tries to resuscitate Yatim.

Shell casings are kicked around by officers as bystanders freely roam the scene of the shooting. The Toronto Sun has pointed out a number of instances in the video that could be viewed as contamination of the scene.

The most disturbing moment comes around the 2:37 mark when the videographer walks to a new position to point his camera at the streetcar door. Yatim's legs are clearly visible and he appears to go through spasms.

Around the same point, an officer can be heard shouting: “Where’s Forcillo? Hey, find me Forcillo. Where's Forcillo?”

James Forcillo was identified Tuesday by various news organizations as the officer suspended with pay in relationship to the shooting.

Soon after the leg twitches, an office or paramedic says "multiple shots, no pulse."

Other video from a security camera near the crime scene which emerged Tuesday also shows Yatim's last minutes, as well as passengers exiting the streetcar. Yatim falls down after being shot in that footage.

A witness who was on the streetcar told CBC Yatim pulled a knife and told the passengers to stay on board. They didn't listen and the witness, Aaron Li-Hill, used his bicycle to block Yatim from getting at the other passengers before exiting the streetcar himself. Li-Hill said Yatim never pointed the knife at him, keeping it facing upward.

Other reports have indicated Yatim exposed himself on the train around the time he pulled the knife.

Various videos of the shooting on the empty streetcar have prompted outrage, public protest and questions about how police should react when a suspect with a weapon is surrounded.

Ontario's Special Investigations Unit is probing the shooting and Toronto Police Chief Bill Blair has said his office will also conduct a review.

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