The state of Berlin approved on Thursday the motion to turn the only largely original GDR police prison on Berlin's Keibelstrasse near  Alexanderplatz into a memorial and educational site.

The first of seven floors will be opened by 2018. Preparatory work for the construction of the other floors is to be carried out in 2018 and 2019. Renovation of the building has to be planned according to requirements for historical monuments.

During the East German communist rule, the former central police headquarters with its prison wing was widely dreaded. In addition to criminals, numerous members of the opposition, critics, refugees and participants in banned protest rallies were imprisoned here. More than 600 prisoners from the Stasi prison in Hohenschönhausen are said to have been interrogated and detained during their detention in the Keibelstrasse prison.

The former prison has been vacant for about 20 years, but was usually closed to the public. Its transformation into a memorial had been disputed for years.

fm/lw/eg (epd, dpa)