A student of criminology who told a neighbour that he was "doing a PhD in murder and Jack the Ripper" was being quizzed for the brutal killing of three prostitutes in Britain.

The man was arrested from his home a red light area where a woman's head inside a rucksack was understood to have been found. Hours later, a woman's body parts were discovered in River Aire in Shipley, West Yorks, Daily Express reported on Thursday.