Is your phone ringing off the hook? Then you’d better check your bank account. According to the Federal Bureau of Investigation, a new “telephone denial-of-service” attack is combining high-tech and low-tech fraud techniques to steal money from the bank accounts of unsuspecting victims.

As reported in the alert issued by the FBI, the scam begins with the suspect obtaining a victim’s personal and banking information, perhaps including bank account numbers, PINs, and passwords. Scammer can obtain a victim’s personal and banking information in a variety of ways, such as through phishing emails, social engineering tactics, or malware surreptitiously installed on a person’s computer.

Once the scammers have the victim’s personal information, they begin tying up the victim’s telephone line by using automated resources to place hundreds or thousands of calls to the victim’s telephone, not unlike a Distributed Denial of Service attack aimed at a computer network that overwhelms a computer with requests for information resulting in a slowing or failure of the network.

While the victim is busy dealing with the onslaught of telephone calls, the scammers quickly drain the victim’s bank account using the previously obtained personal and banking information to gain access to the account. If the banking institution calls its customer to verify the transactions they find the victim’s telephone line to be busy. In some cases, scammers are brazen enough to change a victim’s contact information listed with the bank. As a result, calls from a bank to verify fraudulent transactions are redirected to the scammers. According to the FBI, “[b]y the time the victim or the financial institution realize what happens, it’s too late.”

Although the FBI did not disclose how much money it believes to have been stolen in this matter, it highlighted the case of a Florida dentist who lost $400,000 from his retirement account through such a scam. Based on the Bureau’s alert, it appears that such crimes will continue to increase in frequency.

Ultimately, the telephone calls serve as a diversion to occupy the victim and a barrier to prevent a bank from verifying the authenticity of fraudulent transactions. If you believe you have been targeted in such a scam, or if you believe you have been the victim of any other online fraud, visit the Internet Crime Complaint Center for resources and guidance.