File photo: Protesters hold placards during a demonstration against the ban on Twitter by the Turkish government in Ankara.

Istanbul - The use of the so-called dark web is on the rise in Turkey as users try to go under the radar to avoid a government blockade on the Twitter social-networking site, but the ban is having an impact, causing a decline in the number of Turkish language tweets. Data from the Tor anonymizing network, a means of surfing the web without revealing users' browsing information, showed usage of the system in Turkey had increased from about 28 000 users connecting before the ban to more than 42 000 as of Monday.

Proxy networks, known as VPNs, said there were more than a million downloads of the products over the weekend, as users tapped into foreign-based systems to circumvent the ban.

However, data from the analytics firm Semiocast published by MIT Technology Review showed a steady decline in recent days in the number of tweets in the Turkish language.

At some peak hours, the decline in Turkish language tweets was precipitous, coming in at about 60 percent of the volume of the week prior to the ban.

While Prime Minister Recep Tayyip Erdogan has remained bellicose in his rhetoric against social media, lashing out against other sites like Facebook and YouTube as well, some senior government ministers, including Finance Minister Mehmet Simsek, have admitted the blockade is tarnishing the country's image.

The government's ban on the site has been strengthened since Friday when it first took effect and now includes subsidiary sites of Twitter. The company itself this week said it remained “committed to defending the privacy of our users in Turkey.” Western countries quickly condemned the Twitter block with Douglas Frantz, a US State Department official, comparing it to “21st century book burning” in a blog post.

“There's no place in a democracy for this kind of clamping-down on people's right to free speech,” State Department spokeswoman Marie Harf said.

“Clearly, this is not an action we think the Turkish government should take.” Turkey has local elections on Sunday with Erdogan's Justice and Development Party (AKP) likely to remain the largest party although its share of the vote might decline.

The clampdown on Twitter was made amid growing corruption allegations against the AKP, many of which are spread on social media. - Sapa-dpa