Fake FBI emails targeting an unconfirmed attack is under investigation

(KYMA, KECY/ CNN) - The FBI is addressing reports about unauthorized emails, coming from a legitimate FBI email address, being sent to thousands of organizations about a purported cyber threat.

At least 100-thousand of the emails have hit inboxes and the agency says it is aware of the fake emails.

One of the emails claimed to be a warning from the Department of Homeland Security that the recipient was the target of a "sophisticated" attack.

But the actual DHS cybersecurity and infrastructure security agency made no such warning.

One cyber-security expert says he was unaware of any malicious software embedded in the emails that appeared to be a prank.

The FBI says the emails are the result of a "software misconfiguation."