Dec. 13 (UPI) -- Dozens of businesses, schools, hospitals and other locations throughout the United States reported a series of bomb threats Thursday, which authorities said appeared to not be credible.
Cedar Rapids Police in Iowa posted an alert on Facebook regarding the emailed threats, which included a message that warned of a recruited "mercenary" with an explosive device in the building.
The emails also demanded $20,000 in Bitcoin by the end of the day to call off the threat.
"The Police Department has found NO CREDIBLE EVIDENCE that these emails are authentic. It appears to be a robo-email that has been sent throughout the area hoping to scam businesses out of money," the department said.
Cedar Rapids Police added businesses in surrounding counties may have also received the email.
The threats were known to have been received in cities such as San Francisco, New York, Seattle, Miami, Washington, D.C., as well as other locations throughout the country, CNN reported.
It wasn't immediately clear whether the nationwide threats were connected, but an email sent to an Oklahoma City business and obtained by CNN was identical to the one cited by Cedar Rapids Police.
The NYPD's Counterterrorism Bureau said it was monitoring multiple bomb threats sent to locations throughout the city, adding it also didn't consider the threats to be credible.
Some buildings including Thurston County Courthouse in Olympia, Wash., and the Park Record newspaper in Park City, Utah, were evacuated after receiving the threats but people were later allowed back inside after a search.
Vancouver police Sgt. Jason Robillard also told CNN some businesses in Canada received threats although he wasn't aware of any evacuations.
The FBI's Boston division tweeted Thursday afternoon that it was "aware of recent bomb threats made in cities around the country," adding the agency was in touch with law enforcement to provide assistance.
"As always, we encourage the public to remain vigilant and to promptly report suspicious activities which would represent a threat to public safety," the bureau said.