Investigators are looking into  rare case of  theft involving an office of the  National Database Registration Authority in Karachi.Cop on Wednesday said 1800 Computerized National Identity Cards (CNICs) and a register was stolen  from a  NADRA facility in Landhi area of city.The police said   thief entered and  escaped through roof  of building.They said no CCTV camera was installed in  office that could have  helped him identwhethery thief.The  thief  is said to have left a clue  that  obviously explains motive behind his  crime.According to reports, investigators and staff of  NADRA office found  a sentence written on wall .But investigators think it might be a  trick  to mislead them.