Kazakh National Security Committee officials say seven Russian nationals were detained for illegally crossing the border after their boats were spotted by a Kazakh border guard helicopter patrolling over the Caspian Sea.
Two Russian nationals were wounded by Kazakh border guards when the boats tried to speed away ignoring the border guards' order to stop.
Kazakh border guards say they had to open fire at the boats' engines to stop the boats from fleeing.
The two wounded Russian nationals were taken to a local Kazakh hospital for treatment but their lives were not in danger.
Kazakh authorities were considering whether to open a criminal investigation against the Russian nationals.
No further details on the incident were available.
Based on reporting by KazTAG, KazInform, and Interfax