: : ` ` We have to work together , uniting for peace , '' a woman says at last . Forensic teams are at the scene of the crime . Police are searching for the weapon the gunman used . ` ` This was a calculated , cold - blooded execution , '' the police chief says .
NEW : `` We have to draw together , uniting for peace , '' a woman says at service . Forensic investigators are at the scene of the shooting . Police are searching for the weapon the gunman used . `` This was a calculated , cold-blooded execution , '' Oakland police chief says .