A bomb dropped more than 80 years ago by a German warplane during World War II detonated in Northern Ireland on Tuesday in a controlled explosion that prompted the evacuation of over 400 homes.

The explosive was discovered at a construction site in County Down on Thursday and deemed to be an immediate danger — leading authorities to order nearby residents of Rivenwood to leave their homes.

Once officials had cleared the neighboring areas, police and army experts detonated the decades-old bomb shortly before 4 p.m. — sending a dramatic plume of smoke high into the sky alongside a deafening boom, the Guardian reported.

The specialists built a sand-filled pit to secure the area before triggering the explosion of the 1,100-pound bomb, an airdropped SC-500 used by the Nazis during the second world war, according to the outlet.

The controlled detonation — which officials described as a complex and dangerous mission — was a success with no reported injuries.

“The success of this operation is a testament to the level of skill our military colleagues have,” North Down and Ards District Commander Superintendent Johnston McDowell said.

The affected residents were able to return home following the operation Tuesday. Officials had set up an emergency support center for them while the threat was ongoing.

“I appreciate the disruption that this has caused, however keeping people safe is paramount and we will not take any risks,” McDowell had said of the mandatory evacuations.

The massive explosive was found in Newtownards, about 12 miles east of Belfast, where the Luftwaffe, Germany’s airforce, targeted factories and shipyards during WWII, the Guardian reported.