A policeman stands guard in front of Munich's Deutsches Museum after was evacuated. Photo: Süddeutsche Zeitung

A Munich museum was evacuated after a World War II-era bomb was discovered in a nearby courtyard during construction work.

The unexploded bomb, which was dated to 1944, was found next to the entrance of the 90-year-old Deutsches Museum (German Museum). In total, 600 visitors and 300 staff safely evacuated from the building.

The Local quoted a Munich fire services spokesperson who said that the device’s mechanical detonator means that it did not pose a realistic danger to the public. “It would need a really hard impact to set it off,” he said.

The 250kg American-made bomb was discovered in a courtyard during refurbishment work.
Photo: Bayerischer Rundfunk (@BR24) via Twitter

According to a tweet by Munich police published on Tuesday afternoon, specialists from the explosives disposal unit could not safely defuse the 250kg (550lbs) American-made bomb on site.

“The bomb at the Deutsches Museum could not be defused on the scene. It will be transported away in the evening,” police said.

The explosive was later transported to a secure detonation area under police escort.

Museum director Wolfgang Heckl praised construction workers for their swift reaction.
Photo: Bayerischer Rundfunk (@BR24) via Twitter

Citing police reports on Wednesday morning, Süddeutsche Zeitung wrote that the device was defused without any problems. The German daily reported that the bomb was sawed open and secured. Its unclear if the bomb was detonated in a controlled explosion.

70 years after the end of World War II, unexploded bombs are still routinely found during construction work in German cities such as Munich, Cologne, and Berlin.

Munich’s Deutsches Museum is one of the world’s oldest and largest science and technology museums.

Museum staff got the day off after the bomb scare.
Photo: Bayerischer Rundfunk (@BR24) via Twitter

Die Welt reported that the construction work that led to the discovery of the bomb is part of the museum’s ten-year restoration and refurbishment plan during which parts of the museum will undergo temporary closures.

However, museum officials clarified that there was still plenty for visitors to see during the redevelopment phase.

The institution is due to reopen and return to regular visiting hours on Wednesday.