A grocery store worker told a jury how he "accidentally" dropped a 47lb stone slab onto a 13-year-old girl's head, inflicting fatal injuries.

Abbas Shabir Ali told how the incident happened after the youngster had lured him to an alleyway near his workplace, where she made unwanted sexual advances towards him.

Giving evidence at Bradford Crown Court yesterday Ali denied prosecution claims it was he who enticed Anum Mahmood to the snicket in Bankfoot, Bradford, sexually assaulted her and then strangled and bludgeoned her to death in order to "keep her quiet forever".

The 20-year-old said Anum, from Birmingham who was visiting Bradford with her family, had walked past him at Awami Foods in Broadway Avenue, before telling him "there were some boys calling him."

He told the jury he had eventually gone to investigate her claims at nearby Hope Avenue where he saw the youngster in an alleyway.

He told the court: "I said there is no-one here. Why did you tell me there were people here? "She said: 'I like you and I fancy you'".

Ali - who said he had learning difficulties but described himself as a "good boy" - said he had tried to return to work but the girl had grabbed his arm.

When she then made sexual advances towards him, Ali pushed her backwards, causing her to fall to the ground, he said.

He told how Anum grabbed his ankle, making him "very angry" and he picked up a large stone slab in the alleyway to scare her off.

Ali said he accidentally dropped the 47lb slab but it did not hit her. He picked it up and it slipped out of his fingers once again, he said.

When Neil Davey QC, prosecuting, asked if it hit her Ali replied he did not know and added: "Without looking back I just jogged back to work."

Ali admitted lying to police by saying he had never been to the alleyway because he was "scared and ashamed".

Mr Davey highlighted how a pathologist had earlier concluded that the rock must have hit Anum at least twice to inflict her wounds.

He asked: "Do you have a different explanation for those injuries" to which Ali replied: "No sir."

Mr Davey then asked how marks suggesting she had been strangled had been found on Anum's neck.

Ali said: "The scarf as I pushed her away might have got caught on my buttons or something."

Mr Davey highlighted how this would have produced ligature marks to the rear rather than the front of her neck, as had been found.

Ali, 20, of Thornton Lane, Little Horton, denies murdering Anum Mahmood in July last year.

The trial continues.