New York — Law enforcement authorities say a flurry of bomb threats sent electronically across the country are "NOT CREDIBLE," including those in New York City. Multiple reports Thursday said various states, businesses, medical offices and schools were the target of the alleged threats. Dozens of local police departments from coast to coast said they were investigating, but nothing had been found.
"Searches have been conducted and NO DEVICES have been found," NYPD said. "We'll respond to each call regarding these emails to conduct a search but we wanted to share this information so the credibility of these threats can be assessed as likely NOT CREDIBLE."
NYPD said some 30 to 40 messages were sent to schools, hospitals and other locations in the city Thursday.
The FBI also weighed in on the alleged threats and said agents are in touch with local authorities.
"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," the FBI said. "As always, we encourage the public to remain vigilant and to promptly report suspicious activities which could represent a threat to public safety."
Sources tell CBS News the threats are related to an email which demands a $20,000 Bitcoin payment. The threats appear to be extortion attempts for money or to cause disruption. The email allegedly said, "If you are late with the money the device will detonate."
The NYPD urged the public to "remain vigilant" and report suspicious activity.
Police in other communities offered similar statements about the threats.
"Several area businesses are receiving what appears to be a robo-email saying there is a bomb threat to their business unless they pay money in Bitcoins. We have found no credible evidence any of these emails are authentic. See CRPD Facebook for more details. #Scam," the Cedar Rapids, Iowa, police department tweeted.
"We are currently monitoring multiple bomb threats that have been sent electronically to various locations throughout the county. These threats are also being reported to other locations nationwide and are NOT considered credible at this time," said a statement from the sheriff's office in Palm Beach County, Florida.
Oklahoma City police tweeted, "We're working a number of bomb threat calls in OKC. There have been similar threats called into several locations around the country. No credible threat found at this point. We encourage the public to continue to be vigilant and call with anything suspicious."
The Jewish Community Center in San Francisco was evacuated late Thursday morning, CBS San Francisco reports. The station said the threat appeared to be directed at the San Francisco Fire Credit Union nearby.
The Associated Press reports an evacuation took place at city hall in Aurora, Illinois, the offices of the News & Observer in Raleigh, North Carolina, a suburban Atlanta courthouse and businesses in Detroit.
Officials investigating Thursday's threats point out they are not an isolated event. Federal law enforcement sources said a federal law enforcement bulletin warned of a similar series of bomb threats received between August and November of this year. The bulletin said law enforcement was aware of threats to "academic institutions, commercial retailers and various government entities." Officials warned the threats showed "common characteristics" and used email spoofing services which made their origin harder to track. The bulletin noted "15 states" received the threats which led to the law enforcement warning.
Jeff Pegues contributed to this report.