Protesters erupted outside a Philadelphia police precinct Monday night hours after police shot and killed a man waving a knife. The victim was identified as 27-year-old Walter Wallace Jr. Cellphone video captured a chaotic scene Monday afternoon. Police said they received a call about a man with a knife. Officers at the scene confronted Wallace with guns drawn. “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 Sergeant Eric Gripp, a Philadelphia police spokesman. Police ordered Wallace to drop the weapon but he continues walking toward them. Wallace’s mother is then seen grabbing her son in an effort to intervene, but he breaks away, heading in the direction of the police, who then open fire. The officers fired at least seven shots each, police said, and Wallace was hit in the shoulder and chest. He later died from his injuries at a nearby hospital. Tensions rose as the night wore on, and early Tuesday, an officer was struck by a pickup truck. The officer, a 56-year-old woman, was treated at a local hospital for a broken leg and other injuries, according to Gripp. The pickup truck was found nearby, unoccupied. Police said 29 other officers were briefly hospitalized after being hit by projectiles, including rocks and bricks. More than 30 people were arrested, police said, and multiple businesses were looted throughout the city. Five police vehicles were vandalized along with one from the fire department, they added. The White House is “prepared to deploy” federal resources in response to the unrest, according to Alyssa Farah, the White House communications director. “We’re monitoring the situation closely. If necessary, we’ll be standing by and prepared to deploy federal resources, if necessary,” Farah said on “Fox & Friends” Tuesday. “President Trump will not tolerate any violence directed at America’s law enforcement.” Maurice Holoway, a witness, told CBS Philadelphia that he and several others tried to get Wallace to drop the knife, to no avail. However, he said if police felt they had to shoot, they should have hit him in the leg “or not shoot him at all.” Wallace’s father, Walter Wallace Sr., questioned why officers used deadly force. “Why didn’t they use a Taser?” he asked, according to the Philadelphia Inquirer. “His mother was trying to defuse the situation.” Wallace Sr. said his son had mental health issues and was on medication. “Why you have to gun him down?” Both officers, whose names have not been released, were taken off street duty pending an investigation. Police said the officers were not equipped with Tasers. “I have watched the video of this tragic incident and it presents difficult questions that must be answered. I spoke tonight with Mr. Wallace’s family and will continue to reach out to hear their concerns first-hand, and to answer their questions to the extent that I am able,” Mayor Jim Kenney said in a statement. John McNesby, president of the Fraternal Order of Police Lodge 5, asked everyone to “wait for the investigation to complete and not to meetly vilify the police department.” But Reggie Shuford, executive director of the ACLU of Pennsylvania, said the city “is overdue for a reckoning with the brazenly violent and abusive behavior in its police department. Video from the incident suggests that no one was in immediate danger when officers killed him.” Shuford called for full transparency by city officials. Jericka Duncan contributed to this report.