By Greg Argos

PHILADELPHIA (CBS) — Protesters gathered outside a West Philadelphia police precinct hours after two officers shot and killed a man armed with a knife. The shooting happened in the area of 61st and Locust Streets, just before 3 p.m. Monday.

The mayor’s office has identified the man shot as 27-year-old Walter Wallace Jr. Part of the incident was captured on cellphone video.

On Monday evening, dozens gathered in front of the 18th Police District in West Philadelphia, upset over what happened blocks away just a few hours earlier.

Cellphone video shows the moments leading up to a deadly police-involved shooting, which started out around 2:45 p.m. as a call for a man with a weapon.

“Responding officers witnessed a male on the block. Immediately they noticed he had a knife in his possession and he was brandishing it, and waiving it erratically,” said Philadelphia Police Sgt. Eric Gripp.

On that West Philly block, near 61st and Locust Streets, video shows that man raising his arm as he approaches police.

Less than a second later, both officers open fire.

“Upon being struck, the male immediately dropped the knife and was scooped up by one of the discharging officers who took him into his police car, drove him over to Presbyterian Hospital where, unfortunately, he succumbed to his injuries,” Sgt. Gripp said.

“I don’t know what his demeanor was. I do know something had to be going on that wasn’t normal,” witness Maurice Holoway said.

Holoway says he and others in the neighborhood pleaded with Wallace Jr. to drop the knife but that didn’t happen.

Now he wishes this call to police for help didn’t lead to the man’s death.

“Shoot him in his leg, or not shoot him at all,” Holoway said.

Both Mayor Jim Kenney and Police Commissioner Danielle Outlaw released statements Monday night.

The mayor said, in part, “The Officer Involved Shooting Investigation Unit of PPD will conduct a full investigation. I look forward to a speedy and transparent resolution for the sake of Mr. Wallace, his family, the officers, and for Philadelphia.”

The commissioner added, “I recognize that the video of the incident raises many questions. Residents have my assurance that those questions will be fully addressed by the investigation.”

The Fraternal Order of Police Lodge #5 president, John McNesby, is asking for everyone to “wait for the investigation to complete and not to meetly vilify the police department.”

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