The FBI’s Portland field office says testing by hazardous materials crews has shown no toxic substance on any of the suspicious letters received by Oregon sheriffs on Monday. The FBI’s Beth Ann Steele says there are approximately twenty such known letters that were delivered on Monday, and no evnidence of a visible powder has been found in any of them. Suspicious mail received by sheriff’s offices in Wasco and Hood River counties on Monday led to closures of those offices. Both Wasco County Sheriff Rick Eiseland and Hood River County Sheriff Matt English says the letters they received were forwarded to the Oregon State Police and the FBI. No health issues were reported at either location.