(Reuters) - A rash of bomb threats were sent via email on Thursday to dozens of businesses and public buildings across the United States and Canada demanding payment in cryptocurrency, but none of the threats was immediately found to be credible, law enforcement officials said. ``We are currently monitoring multiple bomb threats that have been sent electronically to various locations throughout the city,'' the New York City Police Department's counterterrorism unit tweeted. At this time it’s unclear if the threats — which have been received in San Francisco, New York, Seattle, Miami, Washington, DC and other locations nationwide — are connected. Across the country, some schools closed early and others were evacuated or placed on lockdown because of the hoax. Director of Communications Anthony Guglielmi tweeted, “#ChicagoPolice are working with federal partners on the investigation, and at this time there is no elevated threat level for the city of Chicago.”

Threats were also emailed to the Charlotte News & Observer and the Raleigh News & Observer newspapers in North Carolina.
Fake bomb threats are sent to dozens of businesses around Canada and the U.S., demanding ransoms in bitcoin. Some of the threats forced evacuations.