GoDaddy.com, the domain site that claims to manage 53 million names, was the victim of a cyberattack Monday by hackers including Anonymous, Twitter accounts said.

The private Scottsdale, Ariz., company's own site was working but sites it operates on behalf of customers were blocked in the late afternoon. GoDaddy has eight large server farms in the U.S. as well as one in India.

The company tweeted it was "aware of the trouble people are having with our site" and urdged customers to monitor Twitter for more information.

"We're working to restore all sevices," a GoDaddy representative said.

In last winter's controversy concerning the proposed Stop Online Piracy Act in the U.S. Congress, GoDaddy was targeted because it supported the law, which was championed by publishers and Hollywood studios. The law remains in limbo in Congress.

Through Twitter, an alleged member of Anonymous claimed to have launched a so-called denial-of-service attack on the company. The hacker, AnonymousOwn3r, tweeted that he'd like "to test how the cyber secuity is safe and for more reasons that I can not talk now."

Last Tuesday, another hacker group, AnitSec, claimed it had obtained passwords and other confidential customer data from more than a million customers of Apple Inc. (Nasdaq: AAPL), the most valuable company. It said it had gotten the data from a laptop used by an FBI agent, who had previously obtained the data from Apple. Both Apple, of Cupertino, Calif., and the FBI denied any leaks or loss of data.

AntiSec, which may stand for "Anti-Security Movement," claimed it was set up in 1999 just as the global computer industry was preparing for the century shift and the feared Y2K bug.

To contact the editor, e-mail: