(Kelso, WA)  --  An investigation is ongoing into the accidental shooting death of a 13-year-old southwestern Washington boy by his friend.  Police say 13-year-old Edgar Vazquez was killed Saturday afternoon when his 13-year-old friend picked up a shotgun, causing it to go off and hit Vazquez.  Vazquez was staying the night at the friend's house in Kelso when the incident happened.  Vazquez's friend told police he thought the gun was unloaded.  Police say they're still looking into whether any laws were broken but that they have no doubt that the incident was an accident.