An anonymous phone call has been placed Tuesday on the emergency 112 hotline, alerting of a bomb at the central Court Hall in downtown Sofia.

The caller has warned about an explosive at the City Court, which is housed inside the building. Everyone has been evacuated and police and bomb squads are checking the premises.

Anonymous bomb threats have become a recent trend, pestering Bulgaria's capital.

On November 9, all Sofia Courts were closed over a bomb alert when the anonymous caller did not say which exact building it would affect.

The 112 hotline was inundated by similar calls last week, particularly for a number of Sofia high schools. They are deemed pranks, and, according to the police, teens placed them because they did not want to attend classes.

Shopping malls have not been spared either. The Serdika Center Mall received bomb threats both on Sunday and Monday and is still closed. On Friday, another central Mall in the capital, The Mall of Sofia, on Alexander Stamboliyski boulevard, received the same threat.

Police and bomb squads have not found traces of explosives in any of these cases.