The discovery of an unexploded World War II bomb near Berlin’s main railway station has disrupted the morning commute for thousands of workers.
Roads have been closed and there are long delays on main railway lines.
Specialists have been called in to decide whether to remove or disarm the 100kg (220-pound) device.
There are thought to be thousands of unexploded bombs buried in Germany. In 2010, three people were killed when one unexpectedly detonated.
Munich blast
A police spokesman said the area surrounding the Berlin bomb, which was found in Heidestrasse, would be cordoned off.
He said the authorities would decide what to do with the bomb at about 09:00 local time (07:00 GMT).
The BBC’s Stephen Evans in Berlin says this device is far from the biggest type of bomb dropped by the Allies or used in Soviet artillery, but it would cause serious damage within a few hundred metres were it to explode.
He says that one of the difficulties is that these bombs are hard to defuse because of rust.
Last year, a bomb was detonated on site in Munich. Even with a wide area evacuated, a large and spectacular explosion caused a fire and much damage to houses.