Google refuted rumors it was hacked on Sunday, following a 15 minute downtime.

Google moved quickly to allay its users' fears. "Google's global properties were unavailable for a short period of time. We have remedied the problem and access to Google has been restored worldwide," the company said in a statement.

However, following reports that some users were being redirected to another site, "SoGoSearch," security experts became increasingly concerned over the possibility of a budding security threat, a contamination of the internet domain name system (DNS).

Speaking to Australian IT, Tom Liston of the SANS Internet Storm Center, shed some light on the situation, saying the most likely explanation was "somebody in charge of Google's DNS did something dumb" and it did not necessarily mean someone had tampered with the DNS system.

"Google went bye-bye for 15 minutes. Or perhaps it was an hour. It depends on who you ask," said Liston.

He went on to explain that some computer systems may have searched for a similar site when there was no response from Google.

Google maintains its unexpected outage "was not a hacking or security issue."

As reported in SC Magazine last month, a malicious website that targets users who make a spelling error when they type in Google.com has been discovered by researchers at anti-virus firm F-Secure.