The Tajik side says Kyrgyz border guards have opened unprovoked gun and mortar fire on their outpost and that a border guard has been killed.
A Tajikistan border guard has been killed in clashes between Tajikistan and Kyrgyzstan, Russia's RIA Novosti news agency has reported, citing the Tajik border force.
Border guards of the Central Asian nations exchanged fire overnight after a fresh dispute regarding the border between the two, officials on both sides said on Wednesday.
The clash, which took place on the eve of a regional security body meeting, started after Kyrgyz border guards accused the Tajiks of taking positions at a part of the border that has not been demarcated.
Both Kyrgyzstan and Tajikistan are allied with Russia and host Russian military bases, but fighting over border issues is frequent and last year almost resulted in an all-out war between the former Soviet republics.
The Tajik side said in a statement that Kyrgyz border guards opened unprovoked gun and mortar fire on their outpost. It said one border guard was killed in the incident and another two were injured, RIA Novosti reported.
Kyrgyz and Tajik leaders are expected to attend a summit of the Shanghai Security Organisation in Uzbekistan this week alongside Russian President Vladimir Putin and Chinese leader Xi Jinping as well as a host of other world leaders.