Ukraine's border guard service says a number of servicemen have been wounded in an insurgent attack on their camp in eastern Ukraine.
In a statement, the Ukrainian State Border Service said that some 100 armed insurgents attacked the border guards' camp in Luhansk in the early hours of June 2.
A gunbattle ensued. A Ukrainian fighter jet was called in for support, RFE/RL reports.
The border service says the number of the attackers eventually swelled to 200.
The fighting is reportedly ongoing.
The conflict between Ukrainian government forces and pro-Russian insurgents in eastern Ukraine has escalated in the last week, with pro-Russian separatists attempting to seize the airport in Donetsk and the shooting down of a Ukrainian military helicopter, killing 14 soldiers.