Around 54,000 people were evacuated from the southern Italian city of Brindisi on Sunday as experts worked to defuse a World War II bomb, authorities said.

Corriere della Sera daily said the operation was the biggest peacetime evacuation in Italy, with more than 60 percent of the city's residents forced to vacate a "red zone" in a radius of 1,617 meters from where the bomb was found.

The British bomb, believed to have been dropped on the city in 1941, is 1 meter long and contains 40 kg of dynamite, authorities said. It was found by chance last month during refurbishment works at a cinema.

The city's airport, train station, two hospitals and a prison were shut down and evacuated as part of the operation, which authorities expect to be completed around lunchtime.