But the inquiry was thrown off course after the three letters and a tape were sent to the investigation team by a man who was to be nicknamed Wearside Jack due to his strong Sunderland accent.
The hoaxer, who had an accent said to be from the Castletown area of Sunderland, sent police three letters and an audio tape at the height of the Yorkshire Ripper inquiry in 1978 and 1979.
While tape can require two to three days to access, RainStor can provide cheap storage that is just 20 to 30 percent slower than online operations access.