During Operation Tigerfish in 1944, the old town hall burned out completely and the entire interior decor was lost. Modern materials were used in the reconstruction of the building. The Old Town Hall was also extended by 3 wings in the plain functional style usual for that time. As a result of the new construction, only the nuns' undercroft of the convent of Poor Clares was preserved. This convent was housed in the former Regelhaus (a quasi-monastic building) "Zum Lämmlein" from 1672 until its abolition in 1782. After that, the buildings were used by the "Hospital of the Holy Spirit".