A court building in a southern Greek city has been closed after a bomb attack that caused serious damage to a prosecutor's office but no injuries.

Police said the building has been cordoned off and was being searched after the Monday morning blast, in the city of Corinth some 80 kilometers (50 miles) west of Athens.

A spokesman for police in the southern Peloponnese region said staff had begun arriving for work when the explosion occurred but were not close to the blast.

Police had received no warning before the attack and refused to comment on the possible motives.