The Internal Revenue Service warned computer users about phony e-mails designed to scare people into believing they are under tax investigation in order to give scammers access to their computer hard drives.

The tax agency said that the e-mail claiming to be from IRS Criminal Investigation falsely states that the person is under a criminal probe for submitting a false tax return to the California Franchise Board. Opening up an attachment to learn more about the complaint allows those behind the scam to gain remote access to the computer.

The IRS stressed that it does not send out unsolicited emails or ask for detailed personal and financial information, including PIN numbers, passwords or other credit card and bank information.

It said that people receiving questionable e-mails should not open attachments or click on any links. Instead, they should forward the e-mails to phishing@irs.gov. It said that since that mail box was opened last year, the IRS has received more than 17,700 emails from taxpayers reporting more than 240 separate phishing or scam incidents hosted in at least 27 countries and the United States.

Other scams try to entice taxpayers to enter a fake IRS web site and ask for bank account numbers or tell taxpayers the IRS is holding a refund for them as a ruse to obtain financial account information.