Protesters clashed with police in Philadelphia, Pennsylvania on Monday evening, as businesses were looted and fires were set following a fatal police shooting just hours earlier. Police say a 27-year-old man armed with a knife was shot and killed by two officers in West Philadelphia Monday. The man has since been identified as Walter Wallace Jr. In the video, two officers are seen trying to get Wallace to drop a knife as he walks around a car. He raises his hand and both officers open fire, shooting at least 14 shots that can be heard in the video.