PHILADELPHIA, Pennsylvania (WJW) – There are multiple reports in Philadelphia that thirty police officers have been injured in riots following a fatal police shooting.

A dozen of those officers required hospitalization for their injuries, according to local reporters.

Thirty people have been detained for the violence, according to WPVI.

Police responded to a domestic call just before 4 p.m. Monday. Video shows officers with guns drawn in a neighborhood.

Initial reports said Walter Wallace was armed with a knife and refused calls to drop the weapon.

You can hear officers yelling, “Put the knife down,” multiple times.

Video shows officers shoot him multiple times. Wallace was pronounced dead at the scene.

A statement released from the mayor and police commissioner says the shooting is under investigation. It does not indicate whether it was confirmed that Wallace was armed.

“I have watched the video of this tragic incident and it presents difficult questions that must be answered,” Mayor Jim Kenney said in a statement.

“I recognize that the video of the incident raises many questions,” said Police Commissioner Danielle Outlaw.

“Residents have my assurance that those questions will be fully addressed by the investigation. While at the scene this evening, I heard and felt the anger of the community.”

Following the shooting, protesters gathered outside a police precinct.

A police sergeant was run over by a truck, according to reporters at the scene.

Other officers were injured when bricks were thrown at them, NBC Philadelphia reports.