Google's Oman Domain www.google.com.on was reportedly defaced few months back due to a hijacking of the company's local domain name by Moroccan Hackers.The Credit was taken by "SQL_Master AND Z0mbi3_Ma" serial website defacers.
It seems that Hacker successfully breached into Oman Telecommunication Company, who is domain registrar of Google's Oman Domain and possible DNS Hijack technique is used to re-direct users to different site whenever they tried to reach Google's local domain.
The text on the hacked site reads as "0h0h0h! U get FUCKED BY! And Z0mbi3_Ma SQL_Master for more: Z0mbi3_Ma@hotmail.com . / Morocco"
Same group of hackers were responsible for hacking The National Security Agency (NSA) in past. Zone H Mirror record also available for proof of hack and at the time of writing, site is defaced.
Source(s): The Hacker News