Google has confirmed previous reports that its own Domain Name System (DNS) service has been intercepted by most Turkish ISPs (Internet Service Providers). A 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.

According to Steven Carstensen, a Google software engineer, Turkish ISPs have set up servers that "masquerade" as Google's DNS service.

"..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. That's essentially what's happened: Turkish ISPs have set up servers that masquerade as Google's DNS service," Carstensen said.

In addition, an Internet monitoring firm said Sunday the DNS service from major communications company Level 3 had also been hijacked. People who try to use Google or Level 3 DNS services are redirected to alternate providers within TurkTelekom, wrote Earl Zmijewski, a vice president and general manager for Renesys, on a company blog.

Turkey's Prime Minister, Recep Tayyip Erdogan, has publicly and repeatedly expressed his dislike of social media, instructing various sites to be blocked.