(Salem, OR) -- Oregon State Police are working to investigate 150 tips that have been received in connection with the death of a young girl in Lincoln County. They still don't know the girl's identity, but they have excluded six missing children. They include 12-year-old Addyson Gibson, of Portland, seven-year-old Noelle Johnson, of Portland and seven-year-old Niayah Bylenga [[ NIE'-uh bih-LENG'-uh ]] from Pendleton or Ritzville, Washington. Investigators are asking that people continue to report tips. They're hoping a sketch of the girl helps identify her.