Think twice about answering e-mail from G-man.

A new Internet scam promising cash for responding to a document request claims to be from FBI Director Robert S. Mueller. The top government cop's request is followed by a second e-mail threatening that "failure to comply will result in charges being brought against the individual by the FBI."

"This e-mail is a hoax," the FBI said in an alert to consumers that was posted Tuesday on its Web site. "Do not respond."

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The same e-mail address, which was not released, was used to send both messages, the FBI said.

The first, claiming to be penned by Mueller, advises recipients that they are eligible for a large sum of money that they can claim with an FBI Identification Record and a Certificate of Ownership. The e-mail includes official information, taken from the FBI Web site, that defines what the records are and how they can be obtained.

The follow-up e-mail appears to be sent from a lower-level FBI official, who demands that a fee be sent to "FBI Nigeria" which will issue the certificate.

"At this point the message becomes more threatening, stating the FBI has investigative programs which can track down those who fail to provide the requested documentation," the FBI said on its Web site.

The spammed scan is the second in as many months to appear to be from Mueller. In September, authorities were alerted to a circulating e-mail, which referenced Mueller's name and office address, that urged recipients to send money to secure prizes won in an international lottery.

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