London’s City Airport was closed Monday, February 12, 2018, following the discovery of an unexploded WWII-era bomb in the River Thames. Metropolitan Police said the ordnance—believed to be a German 500kg fused device—was found at King George V Dock during work at the airport on Sunday and they set up a 200-meter exclusion zone, evacuating properties lying within that zone, and closing nearby roads.
Specialist officers worked with the Royal Navy to remove the device. Approximately 24,000 tonnes of explosives were dropped on London by the Luftwaffe during WWII. Unexploded ordnance from that time is often found by construction crews.