The online encyclopaedia Wikipedia appears to have been blocked in Turkey.
The internet monitoring group Turkey Blocks said on its website that the shutdown is “consistent with internet filters used to censor content”.
In the past Turkish authorities have denied blocking internet sites, blaming technical problems instead.
But monitoring groups say the shutdowns are deliberate and often come after attacks, controversial government moves or demonstrations against the government.
Turkish users attempting to go to the Wikipedia page are receiving a message that the site can not be reached, with a “connection timed out” notice.