Google said Turkey has been intercepting its Internet domain and redirecting users to other sites. The attacks on Google follow the banning of Twitter and YouTube by the administration of Prime Minister Recep Tayyip Erdogan who is being accused of massive corruption.
In a post on Google's security blog, software engineer Steven Carstensen said the company has received "several credible reports and confirmed with our own research that Google's Domain Name System (DNS) service has been intercepted by most Turkish ISPs (Internet Service Providers)."
Carstensen said the DNS server tells your computer the address of a server it's looking for, in the same way that you might look up a phone number in a phone book.
"Imagine if someone had changed out your phone book with another one, which looks pretty much the same as before, except that the listings for a few people showed the wrong phone number," he added.
"That's essentially what's happened: Turkish ISPs have set up servers that masquerade as Google's DNS service."
The news came just days after Turkey banned YouTube after the video-sharing website was used to spread damaging leaked audio files from a state security meeting debating possible military action in Syria. Erdogan angrily attacked his political opponents for leaking the recording.
The attack on Twitter follows the posting and widespread sharing of voice recordings and documents on Twitter that appear to provide evidence of widespread corruption involving Erdogan, his family and political allies. The leaks came from two anonymous sources.
In one recording, Erdogan is heard warning his son to remove money from his and other houses, following the news that police were raiding premises as part of a wide-ranging corruption investigation. Erdogan has claimed the recording is a fake.