Image copyright Essex Police Image caption Killer James Fairweather was arrested in May last year

A teenager fascinated by serial killers has been detained for 27 years for the murders of two strangers in Essex.

James Fairweather was found guilty of stabbing James Attfield and Nahid Almanea to death in Colchester in 2014, when he was 15.

The 17-year-old, from Colchester, admitted manslaughter but denied murder on the grounds of diminished responsibility.

He was convicted last week and given two life sentences at the Old Bailey.

Live reaction: Teen sentenced for double murder

Father-of-four Mr Attfield, who was disabled following a car crash, was stabbed more than 100 times on 29 March in the town's Castle Park.

Saudi Arabian student Ms Almanea, 31, was stabbed with a bayonet as she walked to the University of Essex campus on 17 June.

Image copyright Essex Police Image caption Nahid Almanea and James Attfield were stabbed to death within a few months of each other in 2014

Mr Justice Spencer told Fairweather he could have been looking at a whole life term had he been older when he committed the murders, which he described as "brutal and sadistic."

His "obsessive interest" in serial killers "undeniably fuelled these killings", and it was clear he was "seeking to emulate them" the judge said.

Fairweather appeared to mouth the words "I don't give a shit" as he was sentenced.

The schoolboy killer

Fairweather was arrested in May 2015, after a dog walker saw him hiding in bushes near the same spot he had attacked his second victim.

The teenager, who was wearing latex gloves and carrying a knife, told police he was "going to get my third victim, but there was no-one about."

Documentaries and photos of Peter Sutcliffe, the Yorkshire Ripper, were found in his possession, and he had researched Stockwell Strangler Kenneth Erskine, Ipswich serial killer Steve Wright and US murderer Ted Bundy.

Media playback is unsupported on your device Media caption James Fairweather told police how he carried out the killing [Warning: Graphic description]

Officers questioned and released Fairweather shortly after Ms Almanea's death, as one of 70 people interviewed with a history of knife crime.

He had been convicted of a knifepoint robbery at a shop in January 2014 and was sentenced to 12 months of youth supervision on 26 March. He murdered Mr Attfield three days later.

Essex County Council previously said such an order "does not warrant constant supervision."

Image copyright Facebook Image caption Fairweather was arrested in May 2015, after a dog walker saw him hiding in bushes near the same spot he had attacked his second victim

Fairweather was bullied at school and his defence argued a combination of autism, paranoia and voices in his head made him kill.

He said he was suffering from psychosis, but a psychiatrist cast doubt on the claims.

The court was told Mr Attfield's mother Julie Finch was forced to give up work after her "fun-loving" son's murder, which meant the family had to sell their home.

In a statement, Ms Almanea's brother, Raed Almanea, described his feelings of guilt at not being able to save his sister and said life is now "meaningless" for the family.

Scale of investigation 1,500 police officers involved 10,000 staffing hours

850 witness statements

550 hours of CCTV reviewed

140 knives examined

The year-long operation to catch Fairweather cost Essex Police £2.6m, the Old Bailey heard.

Assistant Chief Constable Steve Worron, Head of the Kent and Essex Serious Crime Directorate, said Fairweather's actions "devastated two families."

"The ferocious nature of the killings had a massive impact on the Colchester community, striking fear and tension among the town's residents for 14 months," he added.