SMS services across Tajikistan have been shut down as authorities brace for a possible opposition rally in Dushanbe on October 10.
The State Telecommunication Service told RFE/RL that the text-messaging problems were caused by unspecified technical problems, but mobile phone operators say the services were shut down on the State Telecom's orders.
Hundreds of websites including Facebook, YouTube, and popular Russian social networks, have been blocked in the Central Asian nation since October 5.
The blockage began after the opposition movement Group 24, led by fugitive businessman Umarali Quvatov, used social media to call for a mass antigovernment protest in Dushanbe on October 10.
Tajikistan's Supreme Court banned Group 24 on October 9, finding it extremist.
On October 10, the prosecutor-general's office offered an amnesty to any Group 24 members who quit the organization.