There were no injuries, deaths or damage, according to preliminary information.
"Last night in the Georgian-South Ossetian conflict zone, near the village of Ergneti, an intense exchange of gunfire was reported," Marat Kulakhmetov said. "A monitoring group consisting of peacekeepers and OSCE representatives is currently investigating at the scene of the incident."
South Ossetia declared independence from Georgia following a bloody conflict in 1991-1992 that killed hundreds of people. The pro-Western Georgian government of Mikheil Saakashvili has said it is determined to bring the breakaway region back under its control.
The commander said the identity of those who initiated the firefight and the consequences of the incident will become clear only after the monitoring group returns, adding that the current situation in the conflict zone is stable.
Irina Gagloyeva, the head of the South Ossetian information and press department, said Georgia began shooting first.
"Without doubt, Georgia initiated the gunfire and South Ossetia returned fire, and only after that did the shooting stop," she said, adding that the shooting began from heavy automatic weapons, which South Ossetia was not supposed to have in the conflict zone.
Last Sunday, South Ossetia reported an attack on its capital, claiming that an armed group of about 10 people moved from the Georgian village of Nikozi towards Tskhinvali and shelled the city's northern district, wounding three people.
Georgia immediately denied reports of the alleged attack on Tskhinvali.
