A 15-YEAR-OLD boy was stabbed through the heart by a 14-year-old "in full view" of pupils leaving a primary school and the people waiting to collect them, a jury has been told.

Alfie Lewis died after he was attacked in Horsforth by another teenager, who went on trial accused of the boy's murder on Monday, prosecutors said.

Craig Hassall KC, prosecuting, said Alfie had been walking down the street to meet friends at the end of the school day when the defendant, who is now 15, attacked Alfie with a 13cm long kitchen knife he had brought from his home.

He said witnesses recalled Alfie looking "surprised and shocked" and saying to the defendant "what are you doing?" as the incident unfolded close to St Margaret's Primary School in Town Street just before 3pm on November 7 last year.

The prosecutor said: "Alfie did not get as far as meeting any of his friends that day.

"He was approached by (the defendant), and stabbed twice - once in the chest and once in the leg.

"He collapsed and died in the road close to the primary school in full view of scores of pupils leaving school and the people who were waiting to collect them." 

Wharfedale Observer: Alfie was 15 when he diedAlfie was 15 when he died (Image: Police)

The prosecutor said a post-mortem examination revealed that the fatal stab injury was a 14cm deep wound to Alfie's chest which punctured his heart.

Mr Hassall told the jury at Leeds Crown Court: "(The defendant) then fled the scene, dropping the murder weapon in the road close to the primary school."

The prosecutor said the defendant has already admitted possessing the knife.

He added: "As we understand it, (the defendant) will accept that Alfie was killed by the knife from his kitchen drawer at home, but will say that, at all times, he was acting in self-defence."

Mr Hassall told the jury of seven women and five men: "But all of the witnesses are consistent however in that none of them suggest that Alfie was in any way the aggressor on November 7.

"None of them suggest that it was that Alfie that attacked (the defendant).

"Several of the witnesses speak of Alfie seeming surprised and shocked at what (the defendant) was doing.

"Several of them recall hearing Alfie ask of (the defendant) 'what are you doing?'"

Wharfedale Observer: Many tributes were paid to Alfie after he diedMany tributes were paid to Alfie after he died (Image: Newsquest)

He said: "None of the witnesses heard Alfie shouting at or threatening (the defendant).

"Insofar as any of the witnesses saw Alfie doing anything towards (the defendant), they describe him trying in vain to defend himself from (the defendant's) knife.

"Several of the witnesses describe deliberate blows by (the defendant) to Alfie."

The defendant, who cannot be named, denies one count of murdering Alfie. He sat next to his father in the well of the court for Mr Hassall's opening statement.

The case continues. 

After his death, Alfie's family paid tribute to him.

A family statement issued through West Yorkshire Police said: "I haven't got the words to describe how devastated we all are.

"Alfie you were one in a million, so funny and an all-round entertainer with your rapping and dancing feet.

"You had the biggest heart and took care of everybody around you. You will never know just how much you are loved by family and friends, and you will always be our uncle Alfie.

"We love you so much. Nothing will ever be the same without you. You will shine in the sky, as bright as you did in all our lives. I love you more than words can say, and you will always be with us forever.

"Love you uncle Alfie."

In the hours following Alfie's death, a sea of floral tributes and candles began to appear at a bench on the green by Broadgate Lane.

The nickname 'Alf' was spelled out with tea lights while a toy monkey and childhood photo were left by loved ones.

The tragedy left an entire community united in shock and grief.

Reverend Nigel Sinclair, team rector at St Margaret's Church, attended a community vigil held for Alfie after his death.

"The whole community is so touched by Alfie's death," Rev Sinclair said at the time.