Cheery 13-year-old Anum Mahmood had taken an innocent liking to the quiet boy who worked in the nearby grocery store. But Abbas Shabir Ali lured her to a secluded alleyway where he sexually assaulted her, then strangled and bludgeoned her to death. Drew Kendell and Anila Baig examine what led the pervert to kill and the shockwaves the murder sent through a close-knit community:

Throughout the first 20 years of his life, there was never a single warning sign of Abbas Shabir Ali's potential for such terrible violence.

Not once did the police have reason to speak to the geeky-looking youth who worked seven-days-a-week at his uncle's shop just 50 yards from his home.

And while Ali did poorly at school, where it was suspected he suffered learning problems, neighbours spoke of a "quiet, respectful and obedient boy" who spent much of his free time at the mosque where his father is a trustee.

After completing his education in the city, the committed Muslim even went to Pakistan to study the Koran.

On Ali's return, many commented on how he lived in the shadow of his more popular, better-looking brother.

But he was to seize the limelight for all the wrong reasons when, at around midday on Sunday, July 21, last year he stepped out of work at Awami Foods and took a two-minute walk to a secluded and little-used alleyway a few streets away.

There, he sexually assaulted 13-year-old Anum Mahmood, strangled her with her own traditional Asian scarf and bludgeoned her with a 21kg slab of Yorkshire stone taken from a nearby garden.

Hours later, after a pair of Jehovah's Witnesses discovered Anum's battered and half-naked body lying face down on the pathway, detectives found Ali across the road, watching forensic experts working behind the police cordons.

Detective Inspector John Armitage, who headed the case, said: "He has been absolutely cold and emotionless since the moment we arrested him there. There has not been one moment of remorse or guilt."

He added: "The whole episode is all the more horrendous because there was no kind of history between them. The pair had never even met before."

Det Insp Armitage said murders usually occurred between people well known to each other in a moment of extreme rage or jealousy.

"I feel that in this instance he targeted this poor girl because she didn't know him and then, in a calculated manner, killed her simply so that she could not identify him.

"We had never had any contact with him and there were never any warning signs as to his behaviour."

Throughout his trial Ali showed no emotion and even claimed Anum had been the one making advances to him - forcing her distraught family to sit through his lies.

Residents around Little Horton and Bankfoot told how the killing had plunged their community into turmoil, raising feelings of mistrust and resentment. Others simply spoke of their shock that Ali could have been capable of such a crime.

One of his close relatives, who refused to be named, said: "He was never a trouble-maker. He didn't achieve much at school in academic terms but he was respectful of his elders and listened to them. This has devastated his family, it is very hard for them."

His uncle, who would only give his surname, Saddiq, added: "Shabir was well-liked and hard-working. I took him on about a year ago and he worked for me for six months. He knew the customers and everyone knew him because he was born and brought up round here. No-one can believe what happened. It is a real shock for the community."

At the time of her murder, Anum had travelled to Bradford with her family from Birmingham to celebrate the birth of a new child. While her mother stayed with relatives elsewhere in the city, Anum stopped at her uncle's home above his shop Ali & Sons because she had cousins her own age there to keep her company.

Anum's uncle, Ashiq Ali, described her as a happy, friendly child and added: "We are utterly devastated."

But as well as the sadness and shock felt across the community, there has also been a strong sense of anger.

Some women complained that the patriarchal nature of the Asian community allowed men to conceal their aggressive behaviour, and even 'gave them a licence' to use violence against them.

Councillor Mukhtar Ali (Labour, Bowling) said the tragedy had torn the community apart.

"The Asian community used to be known for its spirit, for its pulling together, but that has not happened here. I think religious leaders should have made a very strong statement that this behaviour cannot be tolerated."

And he added: "It is something that just incensed me, and I wish the community could pull together so that nothing like this ever happens again.

"In order for the Asian community to be recognised as a strong community, it must be seen to be standing up against violence and acts of criminality."