German construction workers detonated a 550-pound World War II-era bomb in Munich Tuesday night, blowing out windows, lighting small fires and causing the evacuation of nearly 3,000 residents.

The controlled explosion took place shortly before 10 p.m. local time in the city’s bustling Schwabing district. The bomb, which had been used by the U.S. Air Force during the war, was found buried underground near an old bar earlier in the week, the BBC reported, and the controlled detonation was necessary because the device did not have a mechanical fuse, as many munitions at the time did.

No one was injured in the blast, and most evacuees have now returned home.

Der Spiegel reports that the discovery was apparently not an isolated incident:

“Officials in Munich estimate that there are some 2,500 bombs buried in the Bavarian capital alone. There have been four significant discoveries of unexploded ordnance in the city this year. Just one week ago, officials in Nuremberg succeeded in defusing a similar 250-kilogram bomb.”