China : Police identify suspect as year - old Liu Li . ` ` This is a very difficult case , '' the company said . ( CNN ) -- The attack happened on the office building 's fifth floor . One of the four people killed suffered life - threatening wounds .
China : Police identify suspect as year - old Liu Li . ` ` This is a very difficult case , '' the company said . The attack happened on the office building 's fifth floor . One of the four people killed suffered life - threatening wounds .