The Uzbek and Tajik border-protection agencies have blamed each other for a shooting incident in which an Uzbek border guard was severely injured.
Tajik officials say the Uzbek border guard entered Tajik territory on horseback on September 11 and started filming the Tajik side of the border.
After he ignored a command to leave, the Tajik side opened fire.
Uzbek authorities insist the border guard was on the Uzbek side of the border and that Uzbek soldiers did not shoot.
Relations between the two countries are often tense.
Dushanbe and Tashkent stopped direct air flights in 1992 and introduced a visa regime in 2001.
Some parts of the 1,330-kilometer Tajik-Uzbek border are mined, and 16 percent of it remains disputed.
Based on reporting by Interfax and RFE/RL's Tajik Service