Philadelphia police boost presence following shooting

Tension gripped the streets of Philadelphia for a second night on Tuesday following a deadly police shooting of a Black man armed with a knife and described by relatives as suffering from a mental breakdown as he was confronted by law enforcement.

A night after violent unrest and looting in the west Philadelphia neighborhood near where 27-year-old Walter Wallace was gunned down on Monday, hundreds of demonstrators marched again demanding racial justice while police and National Guard troops braced for more disorder.