Italian authorities ordered the biggest peacetime evacuation in the country since World War Two on Sunday to defuse a massive unexploded British bomb that was partially damaged when discovered in the southern city of Brindisi. The historic evacuation displaced some 53,000 residents -more than half - of the coastal city on the Adriatic, due to the high risk that the 440-pound ordnance containing 40 kilograms of dynamite could explode. The chances of detonation were increased after the munition was damaged on November 2 by a bulldozer excavating for a remodel of a cinema.. The bomb is believed to have been dropped on the city in a 1941 air raid, during the period of World War Two when Italy was still allied with Germany and Royal Air Force bombers based in Malta were targeting Naples, Brindisi and Bari in order to disrupt Axis shipping lanes. According to the Italian defence department, it is just one of thousands of unexploded ordnances that still lie dormant and undiscovered throughout Italy. Earlier this month more than 10,000 Turin residents were evacuated for the deactivation of a similar British bomb, as were 4000 residents of the northern city of Bolzano in October. In the month and a half since the unexploded bomb was discovered in Brindisi, city officials put into place a strict evacuation plan with a 1,617 metre "red zone" around the damaged bomb, which was reinforced with an external structure last week. The city's airport, train station, hospitals and prison were shut down as part of the operation on Sunday. By mid-morning the bomb had been successfully defused by a team of more than a dozen Italian army explosives experts, who used a special metal key that was carefully turned with remote-controlled technology, as the mayor and other security officials watched drone footage of the operation from a nearby situation room. The bomb is expected to be set off tomorrow in a remote location outside the city.