By CBS3 Staff

PHILADELPHIA (CBS) — There is a heavy police presence on the streets of Philadelphia Tuesday during unrest in the city following the deadly police shooting of Walter Wallace Jr. in West Philadelphia. Thirty officers were injured during clashes in the neighborhood overnight.

Police have arrested 91 people for rioting, looting, vandalism and assaulting officers.

The city is now bracing for the possibility of more violence tonight as Mayor Jim Kenney promises a quick investigation into the shooting. Police say Wallace was armed with a knife.

Lawyers representing the family of Walter Wallace Jr. condemned the shooting Tuesday afternoon.

They told reporters they believe the shooting was unjustified and say the family had expected an ambulance yesterday afternoon, but police got here first.

Police sources confirm to CBS3 officers responded to the Wallace home in the 6100 block of Locust Street a total of four times on Monday.

Investigators described Wallace as erratically brandishing a knife while approaching officers, who video shows then drawing their service weapons.

The fatal shooting was captured from numerous angles, as Wallace’s mother trailed her son as he walked towards police.

Investigators confirm Wallace was shot a total of 14 times, seven discharges by each officer.

Sources say those officers have been on the force each less than five years and had just left roll call when responding to the Wallace residence. They have since been taken off patrol pending the outcome of an Internal Affairs investigation.

Sources say they’ll report to IA for questioning on Monday.

Attorneys for the family say Wallace’s wife is pregnant and will be induced tomorrow. They are questioning why the state of Wallace’s mental health did not produce a different response by city agencies.

They’ve also questioned why officers were not outfitted with tasers. Neither officer had one on Monday.

“We have a person who has mental health issues. We’re gonna vet those out as the process continues but we have officers who, I think, are not properly trained to deal with those mental health issues. And I’m looking for the special interest groups, where are they? They come out for all the other acronyms, I’m not certain where they are in this particular moment,” said Wallace family attorney Shaka Johnson.

“I do not want to see my city tore down. We don’t need that. You’re not resolving anything for our family. Don’t do this in the name of my nephew because this is not what he would’ve wanted,” said Rodney Everett, Wallace’s uncle.

Wallace was a recording artist and had produced music about police brutality, according to the family’s attorneys.

Numerous demonstrations are planned for tonight. Members of Philadelphia’s Black Clergy gathered Tuesday afternoon just a few yards from where Wallace was shot.

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