Police are on alert after two phone calls by unknown persons warned a bomb had been planted and would go off at the Athens Court of Appeal.

The calls were made at 9:15 am on a news site and warned of a bomb at the Court of Appeals, giving 40 minutes before it would explode.

A few minutes later, at 9.19 a second person phoned a TV station and also warned of an explosive device.

Police have cordoned off the area surrounding the Appellate Court buildings.