Shooting broke out on Wednesday between guards patrolling the border between Kyrgyzstan and Tajikistan, Russian news agencies said, citing the Kyrgyz border service.
While recent years have seen frequent skirmishes along the border, the latest incident follows fighting on Tuesday between two other former Soviet republics, Azerbaijan and Armenia, which was their deadliest since 2020.
The Kyrgyz border service said Tajik guards opened fire after being asked to leave "combat positions" along the border and Kyrgyz guards used weapons in response, Russia's RIA state news agency said.
Reuters was not able to immediately verify the reports.
(Reporting in Melbourne by Lidia Kelly; Editing by Clarence Fernandez)