22 August 2012 Last updated at 11:25 ET

'Yorkshire Ripper interest' of hammer attacker

Fry: Had a hammer with him in both attacks

A teenager who attacked two women in Dorset while armed with a hammer told police he was interested in the Yorkshire Ripper.

One of Stefan Fry's victims was struck on the head with the hammer while another was punched in the face before she fought him off.

Fry, 18, from Bridport, was jailed for four years at Dorchester Crown Court.

The detective who led the investigation said Fry had researched serial killer Peter Sutcliffe.

Det Ch Insp Paul Powley told how officers discovered books on the Yorkshire Ripper in Fry's bedroom following his arrest.

"It would seem he had some kind of keen interest in Peter Sutcliffe which inspired him to commit these crimes," he said.

"He (Fry) is a dangerous individual. In interview he said he was very interested in the Yorkshire Ripper, what he had done and how he had done it.

"There seemed to a pattern that was escalating in violence. People with these obsessions, who engage in this type of offending, usually go on to commit more serious crimes."

Sutcliffe killed 13 women in the north of England throughout the late 1970s and early 1980s.

The lorry driver, from Bradford, was given 20 life sentences in 1981 and was told in 2010 he would never be released from prison.

Mr Powley described Fry as being from a "solid family unit" and said there was nothing to indicate why he carried out the attacks.

'Fought off with umbrella'

Fry's second victim, a 37-year-old woman, was struck on the head from behind with a hammer at Langdon Hill, near Chideock, in February.

The teenager had earlier targeted a 32-year-old woman in Dorchester last December.

Mr Powley said: "He punched her in the face but she fought him off with her umbrella".

When officers attended they found a hammer hanging on a fence nearby.

The supermarket worker had previously been stopped and searched in Bridport by officers in 2010, after a woman reported being followed.

Fry, from Bridport, was caught after the second victim remembered part of his car registration.

He pleaded guilty to two counts of assaults occasioning actual bodily harm and two offences of possessing an offensive weapon.