Hundreds of demonstrators gathered at West Philadelphia Park before marching through the neighbourhood on Tuesday.
They marched peacefully for much of the night, chanting Mr Wallace's name. But when the group encountered a handful of officers near a police station, several in the crowd threw rocks, light bulbs and bricks at the officers.
It comes after Mr Wallace Junior, 27, was shot dead by officers after on Monday afternoon.
Police said he was wielding a knife and ignored orders to drop the weapon before officers opened fire. But his family’s lawyer said that relatives had called an ambulance for help with the father-of-nine's mental health crisis, and that police had already been to his house three times that day.
In the shooting video posted on social media, and viewed over 1.5million times, officers yell for Mr Wallace to drop a knife.
His mother Catherine can be seen following Mr Wallace, trying to get him to listen to officers, as he briskly walks across the street and between cars. It is unclear from the video as to whether he is holding a knife but witnesses said he was.
His mother screams and throws something at an officer after her son is shot and falls to the ground.
Last night a 500-strong group gathered in a West Philadelphia park and marched peacefully for much of the night, chanting Mr Wallace's name.
But when the group encountered a handful of officers near a police station, several in the crowd threw rocks, light bulbs and bricks at the officers.
Social media footage shows police smashing the windows of a car and dragging the driver out. Several hardware stores and a Walmart were reportedly looted.
Police said 30 officers were injured in the skirmishes, including a female officer whose leg was broken when she was struck by a vehicle.
Walter Wallace Senior, the victim's father, held an impromptu press conference in a desperate bid to halt the violence. He said: “I don’t condone no violence, tearing up the city or looting of the city and all this chaos.
“Out of respect to my family and my son stop this violence. People all have their own business and have to eat.
“I feel in my heart justice has got to be done to help my son and my family.
“We’ve got good cops and we got bad that’s the system but someone has to be held accountable for what they done.”
His mother Catherine said she begged officers not to shoot her son.
“I was telling police to stop. ‘Don’t shoot my son, please don’t shoot my son,’” she told reporters. “They paid me no mind, and shot my son.”
The Wallace family’s lawyer, Shaka Johnson, said Mr Wallace’s brother had called 911 to request medical assistance and ambulance.
Wallace suffered from bipolar disorder, and his psychological difficulties were relayed by his wife to the officers who encountered him before the shooting, a lawyer for his family said.
He said: “When you come to a scene where somebody is in a mental crisis, and the only tool you have to deal with it is a gun … where are the proper tools for the job?”
Chief Police Inspector Frank Vanore confirmed the two officers each fired at least seven rounds – at least 14 total shots – but Mr Vanore could not say how many times Mr Wallace, a father of nine, was struck.
Philadelphia police have yet to detail the night’s arrests and injuries. Unrest the previous night had injured 30 officers and led to 90 arrests, they said.
Additional reporting by Associated Press.