frankfurt frankfurt city officials warn germany financial capital could grind halt monday residents heed order vacate home allow defuse massive world war two bomb sunday city evacuate 60,000 people nation big maneuver since war officials disarm british bomb discover build site week frankfurt leafy westend many wealthy bankers live fire police chiefs hastily call press conference friday say would use force incarceration necessary clear area residents uncontrolled explosion bomb would big enough flatten city block frankfurt fire chief reinhard ries tell reporters bomb 1.4 tonnes explosives say fragment problem also pressure create would dismantle build 100-metre yard radius. hc 4000 bomb assume drop britain royal air force 1939-45 war find unusual rarely unexploded bomb large sensitive position compulsory evacuation radius 1.5 km roughly mile around bomb include police headquarter two hospitals transport systems germany central bank store 70 billion gold reserve officials friday call frankfurt residents clear area a.m. sunday warn effort could take least 12 hours police say begin defuse bomb sure everyone leave area would ring every doorbell use heat-sensing technology overhead helicopters help identify stragglers say roads transport systems include part underground close work least two hours bomb defuse allow patients transport back hospitals without traffic air traffic frankfurt airport could also affect easterly wind sunday air traffic control tell reuters friday also small private plan helicopters drone ban evacuation zone say frankfurters spend day shelter set trade fair jahrhunderthalle convention center police say addition museums offer frankfurt residents free entry sunday open doors early morning usual city say website frankfurt evacuate thousands huge wwii bomb defuse