Georgian officials say a police truck was hit by a bomb blast while on patrol in the tense region near the Russian-backed rebel region of South Ossetia.
The Interior Ministry says no one was injured in the explosion on Thursday. It says the blast was caused by a mine with a timer attached.
Tensions have escalated ahead of the European Union's report next week on last year's Georgia-Russia war. Russian forces drove Georgian troops out of both South Ossetia and Abkhazia during the war, and Russia recognizes both separatist regions as independent. Radio Free Europe says EU monitors have recently intensified patrols along the breakaway republics' borders with the rest of Georgia.