A World War II-era bomb was unearthed at Germany's Dusseldorf airport and destroyed in a controlled explosion Monday, causing momentary flight delays.

The bomb, weighing about 275 pounds, was discovered during construction work, reported the Independent. Authorities decided to detonate the bomb on site, prompting them to place it an 26-foot hole, away from the airport's runways to limit collateral damage.

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

The airport said on its Facebook page that the bomb was destroyed at 8:43 a.m., reported U.S. News & World Report. Two departures and five arrival flights were cancelled, and an overall 41 flights were affected due to the discovery and subsequent detonation.

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

This isn't the first time a bomb has been found near Dusseldorf. In 2009, a 500-kilogram bomb was unearthed near the site and destroyed, according to the AFP.

Undetonated bombs from World War II are still being found all over Europe, despite the war ending seventy years ago. They're usually unearthed during construction work, often leading to mass evacuations.