Think of it as one more reason not to write checks. Hackers believed to be operating out of Russia have figured out a high-tech way to carry out the decidedly low-tech crime of check fraud, a computer security company says - writing at least $9 million in fakes against more than 1,200 legitimate accounts. But these hackers got the account information in an unusual way: They broke into three websites that specialize in a little-known type of business - archiving check images online. Check counterfeiting is a crime that savvy Internet criminals usually pass up. After all, it's far easier for them to make money by stealing credit cards and online banking passwords. The scam was discovered by SecureWorks Inc., an Atlanta computer security company. The organization says it is working with the FBI and says the hackers have not been caught. Retailers and other businesses use the sites to store records of all the checks they write. Check-cashing operations use them to sock away images of checks they receive. And some banks pay them to store images of customers' checks, so the customers can see them when they log in to their online banking accounts. The criminals downloaded all the images they could find, grabbing bank routing numbers, names and addresses and even signatures of legitimate account holders. They used the information to create their own checks using easy-to-acquire software and printers. Because all the account information is real and the victims don't know their accounts have been compromised, the odds of the checks going through are high. SecureWorks notified the three sites and said they have closed their security holes, but warned that the scam is ongoing and targeting other, similar sites. The research was being released in conjunction with the Black Hat computer security conference in Las Vegas, which runs Wednesday and Thursday and draws security professionals from around the world to hear about the latest vulnerabilities and attacks and ways to thwart criminals. Notable presentations this year are to include a demonstration of how to break into widely used ATMs, a talk that was pulled last year by the researcher's employer after complaints from the ATM maker. Researchers are also expected to discuss vulnerabilities in smart phones and in the technology used to secure online transactions. A consistent theme at Black Hat, and at the related DefCon conference this weekend in Las Vegas, is that most Internet criminals are now motivated by money rather than mayhem.