The Tajikistan government ordered Internet providers on Saturday to block Facebook, along with several independent media sites, a spokeswoman for the country's web-provider association told AFP.
"Internet providers received a spoken order from government agents to block the sites," said Parvina Ibodova, president of the association.
"We are minions. We get our licences from the authorities and that's why, as though we were circuit breakers, we are obedient and cut access to the sites."
Ibodova said about a dozen Internet providers had since Saturday blocked access to Facebook and several independent sites including tjknews.com and centrasia.ru.
The government's communication agency declined to comment.
Tadjikistan is a former Soviet republic in Central Asia that borders Afghanistan. The poorest of the former Soviet nations, it has been ruled with an iron fist by Emomali Rakhmon since 1992.
Ibodova said she did not know if the decision to block the sites was political, adding she had been told it was for technical and security reasons.
The blocked sites regularly publish articles critical of Rakhmon's regime.