Updated

Following a wave of negative publicity and pressure from the government, several Web sites that peddled people's private phone records are calling it quits.

"We are no longer accepting new orders" was the identical announcement posted Wednesday on two such sites, locatecell.com and celltolls.com.

"Thank you for your patronage. It was a pleasure serving you," the sites said.

The Federal Trade Commission this week conducted a sweep of 40 sites known to have been selling private phone records. According to the FTC's Lydia Parnes, more than 20 sites have recently shut down or stopped advertising for new business.

The agency has sent letters to about 20 other sites, warning them that they may be violating the law and should review their business practices, said Parnes, director of the FTC's Bureau of Consumer Protection.

Parnes, who testified before a Senate subcommittee on consumer affairs, said the commission also has a number of ongoing investigations into the sales. She did not elaborate.

While some sites appear to be closing up shop, others have seen a boom in business with the recent media attention, said Marc Rotenberg, executive director of the Electronic Privacy Information Center.

Rotenberg urged lawmakers to ban a practice known as "pretexting," in which data brokers or others call a phone company, impersonate a customer and then persuade the company to release the calling records. Those records usually include whom a person called, who called them and the duration of the calls.

In one case that received a lot of attention recently, a blogger was able to buy the phone records of former Democratic presidential candidate Wesley Clark. All the site needed, it said, was Clark's cell phone number and a credit card payment of $89.95.

Pretexting for financial data is illegal, but there's no specific law against pretexting for phone records. Broader fraud laws can be used to prosecute the companies but several witnesses at the hearing suggested a specific law could help halt the shady sales.

Lawmakers in both parties expressed outrage over the practice.

"This is fraudulent and criminal activity that must be prosecuted and must be stopped to protect innocent people," said subcommittee chairman George Allen, R-Va. Allen and Sens. Ted Stevens, R-Alaska, and Mark Pryor, D-Ark., are expected to introduce legislation Thursday that would outlaw pretexting for phone records.

The Federal Communications Commission is also investigating online data brokers. It has subpoenaed about 30 companies for information on how they are obtaining the phone records.

The FCC also is expected to consider whether to tighten rules governing the nation's phone carriers and how they handle customers' calling records.