(Washougal, WA)  --  Clark County authorities say they've arrested a suspect in connection with the death of a 78-year-old woman in Washougal [[ wash-OO-gul ]].  Investigators say 27-year-old Benjamin W. Walker has been charged with first-degree murder after the victim was found dead during a welfare check at a home on H Street early yesterday morning.  Officials haven't released the woman's name.