NSI officials said some surfers are being sent to the Internet Corporation for Assigned Names and Numbers, or ICANN, and the Internet Council of Registrars, or CORE, sites when they type in NSI addresses such as nsi.com and netsol.com. The hack took place amid a political battle to determine who should keep track of domain names. Network Solutions has had a monopoly on the registration process, but the U.S. federal government is opening up the field to other competition, such as CORE. ICANN, a non-profit body is taking over administration of the Internet addressing system, a process NSI had taken a role in handling. NSI officials said the problem should be fixed by mid-morning Saturday, and they're working with the FBI to track down the hackers. "Hopefully we'll be able to track down the perpetrators, but hackers, especially at this level, are fairly sophisticated," NSI spokesman Brian O'Shaughnessy said. O'Shaughnessy said the break-in was similar to a hack in 1997, when the operator of an alternative domain keeper redirected traffic to his site. He pleaded guilty to one count of computer fraud. NSI officials said the hacks at first appeared to come from SoftAware, a Marina del Rey, California Internet service provider located in the same building as ICANN, but they cautioned that the hackers can mimic addresses in order to trick authorities. NSI said the move hadn't affected business yet because more than 70 percent of its registrants are handled by its business partners.