Authorities across the country say scammers are sending threatening emails to businesses and schools demanding payment to a Bitcoin account.
The emails, which claim there is an explosive device inside the building, are not credible, police say.
The scam has been reported in Portland, Clackamas County, Hillsboro, Vancouver, McMinnville, Eugene and Medford.
The sender claims the Bitcoin payment will prevent the explosives from being set off, and there are “recruited persons” watching the building for any sign of evacuation or police.
No suspicious devices have been reported so far, according to police.
“It appears that the author is not a native English speaker, which is seen a lot in mass scams,” McMinnville police said in a news release.
The FBI's Portland office released the following statement about the threats:
We are aware of the recent bomb threats made in cities around the country, and we remain in touch with our law enforcement partners to provide assistance. As always, we encourage the public to remain vigilant and to promptly report suspicious activities which could represent a threat to public safety.