A 100m2 area was cordoned off after the bomb was found near the Sonnenhof old people’s home at around 2.45pm in the afternoon, Zurich cantonal police said in a statement.
Personnel from the Swiss army’s Kamir bomb squad and from the Zurich Forensic Science Instituteinvestigated the unexploded bomb before giving the all-clear for residents to return to their homes.
The device measuring 70 centimetres and weighing 25 kilograms was an aircraft bomb using for testing purposes in 1938/1939, according to Zurich police.
A helicopter, the fire brigade and ambulance services were all on hand during the operation on Tuesday afternoon.
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