NEW YORK (AP) - It's unclear whether it was a hacker or something else - but one thing is clear: a whole lot of web sites run by were down for hours Monday.

The problem was a huge headache for the many small businesses that rely on Go Daddy for Web hosting services. Still in question is who or what was behind the outage.

A Twitter feed that claimed to be affiliated with the "Anonymous" hacker group said it was behind the outage - but that is unconfirmed. Another Twitter account, known to be associated with Anonymous, suggested the first tweet was just taking advantage of an outage it had nothing to do with. hosts more than 5 million Web sites, mostly for small businesses.