Officials say around 1,000 people have been evacuated after an unexploded bomb was found during construction work in north-eastern Czech Republic.

Police spokeswoman Sona Stetinska said the discovery of the bomb that weighs several tens of kilograms (pounds) in a densely populated neighborhood in the city of Opava prompted the evacuation Monday afternoon. Stetinska said several nearby roads and streets also had to be closed.

Opava City Hall said the bomb is likely from World War II. It said police experts have started to defuse it.

Bombs left over from World War II are discovered from time to time in the region and elsewhere in the Czech Republic.

Police didn't immediately give any further details.