Police officers stay in front of the main train station in Berlin, Germany, Friday, April 20, 2018. Berlin police are evacuating thousands from a central area of the German capital and shutting down the main train station in preparation for the removal of an unexploded World War II bomb found during recent construction work. (AP Photo/Michael Sohn)

An information board is pictured at the main train station in Berlin, Germany, Friday, April 20, 2018. Berlin police are evacuating thousands from a central area of the German capital and shutting down the main train station in preparation for the removal of an unexploded World War II bomb found during recent construction work. (AP Photo/Michael Sohn)

Empty stairs are pictured at the main train station in Berlin, Germany, Friday, April 20, 2018. Berlin police are evacuating thousands from a central area of the German capital and shutting down the main train station in preparation for the removal of an unexploded World War II bomb found during recent construction work. (AP Photo/Michael Sohn)

Interior view of the evacuated main train station in Berlin, Germany, Friday, April 20, 2018. Berlin police are evacuating thousands from a central area of the German capital and shutting down the main train station in preparation for the removal of an unexploded World War II bomb found during recent construction work. (AP Photo/Michael Sohn)

Interior view of the evacuated main train station in Berlin, Germany, Friday, April 20, 2018. Berlin police are evacuating thousands from a central area of the German capital and shutting down the main train station in preparation for the removal of an unexploded World War II bomb found during recent construction work. (AP Photo/Michael Sohn)

Policemen ring bells at a house that is to be evacuated due to the disposal of a World War II bomb close to the Hauptbahnhof main railway station in Berlin's Mitte district on April 20, 2018. The planned disposal of the unexploded World War II bomb will force a mass evacuation around Berlin's central railway station and likely spark transport chaos in the German capital. / AFP PHOTO / Odd ANDERSEN

A policeman looks on as a woman pulls a suitcase through a street that is to be evacuated due to the disposal of a World War II bomb close to the Hauptbahnhof main railway station in Berlin's Mitte district on April 20, 2018. The planned disposal of the unexploded World War II bomb will force a mass evacuation around Berlin's central railway station and likely spark transport chaos in the German capital. / AFP PHOTO / Odd ANDERSEN

Policemen stand in front of a house that is to be evacuated due to the disposal of a World War II bomb close to the Hauptbahnhof main railway station in Berlin's Mitte district on April 20, 2018. The planned disposal of the unexploded World War II bomb will force a mass evacuation around Berlin's central railway station and likely spark transport chaos in the German capital. / AFP PHOTO / Odd ANDERSEN

Policemen stand in a street that is to be evacuated due to the disposal of a World War II bomb close to the Hauptbahnhof main railway station in Berlin's Mitte district on April 20, 2018. The planned disposal of the unexploded World War II bomb will force a mass evacuation around Berlin's central railway station and likely spark transport chaos in the German capital. / AFP PHOTO / Odd ANDERSEN

Policemen stand in a street that is to be evacuated due to the disposal of a World War II bomb close to the Hauptbahnhof main railway station in Berlin's Mitte district on April 20, 2018. The planned disposal of the unexploded World War II bomb will force a mass evacuation around Berlin's central railway station and likely spark transport chaos in the German capital. / AFP PHOTO / Odd ANDERSEN

A woman with a suitcase leaves a house that is to be evacuated due to the disposal of a World War II bomb close to the Hauptbahnhof main railway station in Berlin's Mitte district on April 20, 2018. The planned disposal of the unexploded World War II bomb will force a mass evacuation around Berlin's central railway station and likely spark transport chaos in the German capital. / AFP PHOTO / Odd ANDERSEN

A woman with a suitcase leaves a house that is to be evacuated due to the disposal of a World War II bomb close to the Hauptbahnhof main railway station in Berlin's Mitte district on April 20, 2018. The planned disposal of the unexploded World War II bomb will force a mass evacuation around Berlin's central railway station and likely spark transport chaos in the German capital. / AFP PHOTO / Odd ANDERSEN

A police car stands in the security zone that is evacuated due to the disposal of a World War II bomb close to the Hauptbahnhof main railway station in Berlin's Mitte district on April 20, 2018. The planned disposal of the unexploded World War II bomb will force a mass evacuation around Berlin's central railway station and likely spark transport chaos in the German capital. / AFP PHOTO / Odd ANDERSEN

19.04.2018, Berlin, GER - Hinweis zur Bombenentschaerfung am Berliner Hauptbahnhof auf einem Zugzielanzeiger des S-Bahnhof Messe Nord/ICC. (Anzeige, Anzeigetafel, aussen, Aussenaufnahme, Bahn, Bahnhof, Bahnhofssperrung, Bahnstation, Bahnsteig, Bahnverkehr, Berlin, Bombe, Bombenenschaerfung, Bombenentschдrfung, Bombenfund, deutsch, Deutschland, Europa, europaeisch, Hauptbahnhof, Hinweis, Information, Kaukasier, kaukasisch, LED-Tafel, Menschen, Messe Nord/ICC, oeffentlicher Personennahverkehr, OEPNV, Personen, QF, Querformat, S-Bahnhof, Sperrkreis, Sperrung, Verkehr, Westeuropa, Wirtschaft, Zugzielanzeiger) 180419D800BERLIN.JPG *** 19 04 2018 Berlin, Germany Note on the bomb attack at the Berlin main station on a train destination indicator of the S Bahnhof Messe Nord ICC Advertisment outside of the station Outdoor shot Railway station Rai