Extortion emails carrying bomb threats cause panic across the US

Police in New York, Chicago, Detroit, San Francisco, and Washington tell Americans to stay calm.

US law enforcement authorities are urging Americans to remain calm after a massive spam campaign carrying bomb threats has scared people and caused building evacuations all day across the country.

The source of all problems is a spam campaign that got underway today, and which was sent to millions of email inboxes, primarily in the US.

The emails had different subject lines and various text variations, but all carried the same threat. Extortionists threatened to blow up a person's workplace or building unless the person paid the equivalent of $20,000 in Bitcoin to a specified Bitcoin address. A screengrab of one of these emails is available in the tweet below.

The emails are obviously fake. Since May, there's been a rash of email extortion campaigns, carrying different themes, but mostly using the classic "sextortion" scheme.

But while security researchers are aware that these types of emails are just false threats, most Americans are not.

Throughout the day, there have been bomb threats reported to authorities all over the US, and local police were forced to evacuate buildings and send bomb squads to investigate.

Universities, schools, media organizations, courthouses, and private businesses all reported receiving the bomb threats. Public institutions were evacuated as a precaution, disrupting the activity of municipalities all over the US.

The most high-profile evacuation reported so far was the Los Angeles headquarters of Infinity Ward, the company behind the Call of Duty game series.

Local police and federal authorities have been swamped with phone calls all day. Authorities from New York, Chicago, Detroit, Las Vegas, Oklahoma City, San Francisco, and Washington have taken to social media to tell users to ignore the emails.

Authorities and security experts advise users on the receiving end of these emails to not panic and not pay the ransom demand.

Security researchers tracking the Bitcoin addresses spotted in today's spam campaign said they haven't seen anyone make a payment yet.

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