In Germany, about 65,000 Frankfurt residents have left their homes for the day to allow experts to defuse a massive unexploded bomb from World War Two. Police said, the defusing operation has begun following the biggest evacuation in post-war German history.<br/><br/>Police said, they have checked every designated house with heat-detection technology to make sure everyone was out. The evacuation area in the Westend district includes hospitals, nursing homes and Germany's central bank. The bomb disposal operation is expected to take about 12 hours. <br/><br/>The 1.4 tonne British bomb was found on a building site on Wednesday. There are believed to be hundreds of thousands of unexploded wartime bombs across Germany. An average of about 2,000 tonnes of unexploded ordnance are found each year in Germany. <br/><br/>It is estimated that about half the 2.7 million tonnes of bombs dropped by Allied powers during World War Two landed on German soil. Many of the bombs were equipped with malfunctioning time-delay fuses, and many never went off.<br/><br/>