Problem in the united states for many years. there were 167 such incidents last year alone, when four or more people were killed with firearms in public not connected to underlying criminal activity. the issue is extremely polarising. many want to see greater restrictions on access to firearms, whilst others are adamant that the second amendment right to bear arms means there should be no or very few restrictions to gun ownership. in california, the hunt for the killer goes on. no description has been offered and the suspect remains at large. david waddell, bbc news. los angeles county sheriff...