The Yorkshire Ripper is being questioned over 17 unsolved cases – including brutal hammer attacks – which happened in the 1970s and 1980s.
Peter Sutcliffe was quizzed by detectives at HMP Frankland in Durham, it has been reported.
The incidents are thought to be similar in nature to the horrific murders and attacks committed by Sutcliffe during his killing spree in West Yorkshire, in which he murdered 13 women and attacked several others.
Sutcliffe killed Huddersfield sex worker Helen Rytka – whose body was found at a timber yard behind the Great Northern Retail Park – and attacked Theresa Sykes in Reinwood.
West Yorkshire Police officers are expected to return to Durham prison later this month to further question the serial killer.
It follows a cold case review after a 2015 book linked Sutcliffe to 23 unsolved murders, including that of a Playboy bunny girl.
The cases are thought to include that of Tracy Browne who was hit a number of times with a hammer when she was 14 in Silsden, near Bradford, in August 1975.
Detectives are also probing an attack on Gloria Wood who was hit with a claw hammer aged 28 on playing fields in Bradford in 1974.
West Yorkshire Police have yet to comment.