An explosive device was thrown at a pub in the centre of Montenegro's capital Podgorica, during last night damaging the nearby Bulgarian embassy, Montenegro's state RTCG TV reported.
The windows and a door to the Bulgarian Counsel's office were broken.
The police came to the scene and later said the Counsel would repair the damage without further investigation.
There was no information on any injuries.
The TV said the loud explosion upset people living in the neighbourhood.