BERLIN — Residents in two German cities are evacuating their homes as authorities prepare to dispose of World War II-era bombs found during construction work this past week.

About 21,000 people were ordered to leave their homes and workplaces in the western city of Koblenz as a precaution before specialists tried to defuse a 1,100-pound U.S. bomb Saturday afternoon.

Among those moved to safety were prison inmates and hospital patients.

Officials in the financial capital Frankfurt, meanwhile, are carrying out what is described as Germany’s biggest evacuation, though similar operations are common even 72 years after the war ended.

More than 60,000 people were ordered to leave a radius of nearly a mile around the site where a 1.8-ton British bomb will be disposed of Sunday.