Jurgen Klopp's press conference interrupted by discovery of World War II bomb outside Borussia Dortmund ground

A 250 kg unexploded bomb was found near Westfalenstadion

Borussia Dortmund coach Jurgen Klopp's press conference ahead of this weekend’s game against Schalke had to be postponed after an unexploded World War II explosive device was found near the Westfalenstadion stadium.

The discovery of the 250kg device triggered a large-scale evacuation over a quarter-kilometre radius as bomb disposal teams were called to the scene. The bomb was found in a parking area to the west of the Signal Iduna Park after viewing aerial photographs.

#dobombe der Evakuierungsradius um den Fundort beträgt 250m, weitere Infos & Karte: http://t.co/DRTA8lW3Xk pic.twitter.com/TBgZ4qG5Uw

— Stadt Dortmund (@stadtdortmund) February 26, 2015

Dortmund authorities shut their Fan World space and club museum immediately after the discovery and issued a brief statement saying, "It is not yet known how long the stadium area will remain off limits.”

The authorities expect the bomb to be defused and the area to be made safe by 14:00 hours CET, and the club is expected to be able to continue their preparations for the weekend's derby.

Dortmund would be hoping that the incident doesn’t affect their recent turnaround in form after enduring a horrible start to the season.

Discovery of such unexploded bombs is common throughout Germany and especially Dortmund, which was subject to heavy bombing by the Allied and Soviet forces during the second World War.