An unidentified family of malicious code destroyed data on nearly 800 computers in the City of Norfolk, Virginia. The software appears to have been designed to trash vital operating files in the WindowsSystem32 folder on the infected machines. IT specialists for the city found that the distribution point for the malware within the citys network was a print server that handles printing jobs for Norfolk City Hall. An exact copy of the malware on that server may never be recovered, as city computer technicians quickly isolated and rebuilt the offending print server.”]
Source: https://krebsonsecurity.com/2010/02/time-bomb-may-have-destroyed-800-norfolk-city-pcs/