fb-pixel Skip to main content

SEATTLE — New technology has led to an onslaught of Internet-inspired fraud tactics that try to use telephone calls to dupe millions of people or to overwhelm switchboards for essential public services, causing deep concern among law enforcement and other groups.

People, businesses, and government agencies across the country are combating the new schemes, in which scammers use the Internet to send a disabling number of calls at the same time. Many of the attacks bombard individuals with automated requests for personal data, in a variation of their e-mail-scam cousins. Others are more vicious, flooding entire phone systems when demands are not met, similar to some attacks against websites.


“You can blast out 100 million calls from the comfort of your keyboard,” said Kati Daffan, a lawyer at the Federal Trade Commission.

In October, the Department of Homeland Security advised federal agencies, local governments, and other organizations to be prepared for so-called denial of service attacks, which flood phone systems with calls, making them unusable. The warning came after attacks against a sheriff’s office in the South and another against a Coast Guard cutter. The department said there had been over 200 such attacks identified against public sector groups.

As they are for most forms of Internet fraud, the latest phone schemes are also difficult to investigate because of their frequency, layers of anonymity, and global nature. Several investigators could not name a successful prosecution of the latest wave of phone swindles, though cybercriminals who committed other forms of fraud have been arrested.

In Tarrant County in Texas, the phone lines of several emergency dispatch centers were disabled in the last year because of a surge of automated calls, said Wanda S. McCarley, director of operations for the Tarrant County 911 District, which includes Fort Worth. The attacks lasted up to an hour and were aimed at 10-digit emergency phone numbers at the centers, which are accessible to callers outside the area, rather than 911 lines, which are not.


Something similar happened to a Texas hospital two years ago, when an intensive care unit’s phone lines were disabled for about six hours, said the chief information officer for the hospital chain that owns the facility, who spoke on the condition that he not be named to avoid unwanted attention for his employer. To defend itself, the hospital started using a service from SecureLogix, a telephone security company, which the hospital’s chief information officer said had been effective.

In both cases, employees at the facilities were contacted by callers who said they were debt collectors seeking repayment of loans taken out by the workers. If the employees did not pay up, the callers threatened, the lines at the employees’ workplaces would be brought down. The attackers then overwhelmed the lines with repeated calls, causing busy signals for legitimate callers.

It is not clear how or why the specific employees were chosen, though law enforcement officials believe that swindlers in such cases may find names on public staff directories or professional sites like LinkedIn.

Some pay up in such swindles, often out of uncertainty about whether they owe the money or to avoid embarrassment at their workplaces, law enforcement officials said. Ralph A. Gagliardi, agent in charge with the Colorado Bureau of Investigation’s identity theft and mortgage fraud units, said he traced payments from the victim in one such attack in Colorado to Nigeria via an intermediary in Florida.


Michael J. McKeown, supervisory special agent for the FBI in Pittsburgh, said, “If people do pay, that makes their problems stop, but it may make it more lucrative for people to do this.”

Automatic dialing software and Internet phone services make it easy to place huge volumes of calls from anywhere in the world. Often, swindlers create messages in a synthesized voice and say they are from a financial institution. The call prompts the recipients to enter personal data through their phone keypads.

Because making phone calls over the Internet is so inexpensive, the practice can be lucrative even if only a tiny percentage of the people provide information. Personal financial data obtained this way can be easily sold on the black market.

Financial and government officials say it is unclear how much money is lost to such schemes.