(Vancouver, WA)  --  Police say they've arrested a man who walked into a Vancouver mental-health clinic with a gun.  A SWAT team and crisis investigators were dispatched to the Northeast 144th Street clinic around 10:00 a.m. yesterday after the man entered the building with a rifle.  No shots were fired and no one was injured.  Authorities say 39-year-old Gregory Castro surrendered and was booked into the Clark County Jail.