A man walks past a vintage U.S. C-54 aircraft at the former Berlin-Tempelhof airfield in Berlin.

A World War II bomb was destroyed in a controlled explosion Monday at the main international airport in the western German city of Duesseldorf, briefly halting air traffic.

Flights at the hub, Germany’s third busiest in terms of passengers, were interrupted for an hour in the morning while the 125-kilogramme bomb was neutralized, the airport said in a statement.

Two departing flights and five arrivals were axed from the schedule and 34 other flights had to be brought forward or delayed on safety grounds, an airport spokesman said.

The bomb had been discovered overnight near the main runway during construction work. Before it was exploded, the bomb was placed in an eight-meter deep hole to limit any collateral damage.

“The bang of the detonation could be clearly heard near the airport,” the city said in a statement.

Authorities fear other bombs might still be hidden beneath the earth at Duesseldorf airport and further digs are planned this month to comb the grounds for WWII-era explosives.

In 2009, a 500-kilo bomb was unearthed near the site and destroyed.

Seventy years after the end of fighting, parts of Germany remain riddled with unexploded bombs from the Allied campaigns, and construction workers regularly uncover them, often leading to mass evacuations.