A schoolboy from Harold Wood has been convicted of murder after stabbing a teenager through the heart on a busy bus.

The 16-year-old, who cannot be named for legal reasons, was this afternoon found guilty at the Old Bailey of murdering Derek Boateng on a packed 393 in Highbury New Park in April.

During the trial, jurors heard how he boarded the bus, pushed past horrified passengers, including a woman holding a baby, and stabbed Derek – who was celebrating his 16th birthday – with a kitchen knife, before jumping off

Derek, of Graham Road, Hackney Central, remained standing for a minute or so, before collapsing “as though he had been hit by a train”.

He was airlifted to hospital but died the following day.

Tom Kark, prosecuting, said: “This is a very sad case for all concerned. It’s tragic for the young boy Derek who lost his life. Terrible for members of his family and terrible for what it means for the defendant who, by any view, took the life of another.

He added: “This boy’s death would never have happened if the defendant didn’t draw his knife.

He described how the knife had pierced Derek’s clothing, sternum and cartilage to reach his right ventricle, causing him to die of massive internal bleeding.

“The single wound which killed him was caused by this defendant, and the blade penetrated the right lower part of his chest and pierced, unfortunately, the right ventricle of his heart.

“As a result, Derek Boateng suffered massive internal blood loss and although he remained conscious...in fact, remained standing for a minute or so, he quickly fell into unconsciousness and his heart stopped.”

Mr Kark said it appeared that there had been some sort of previous dispute between the two boys.

“Whatever had gone on before, we say this was a senseless act of violence,” he said.

“It resulted in the tragic and untimely death of a young boy.”

The defendant admitted stabbing Derek but claims he was acting in self-defence – both boys had drawn a knife and witnesses described them slashing at each other – but jurors rejected the claim.

An eye witness, Sian Harrington, said: “It was as though he had been hit by a train. He collapsed and fell back in his seat with his head against the window

“Myself and another woman decided we would try and lay him down. We didn’t know what had gone on and I thought he was in shock or fitting.

She added: “I thought to myself, ‘it’s happening. I am on a bus in London and someone has a knife’.”

Det Ch Inspector Chris Jones, of the homicide and major crime command, said: “This was an appalling attack on a crowded bus. It is dreadful to think that Derek, who was celebrating his 16th birthday, lost his life over nothing more than a brief clash with another teenager.

“This dreadful tragedy has left a family grieving for a much-loved son, brother and friend who had everything to live for. The incident has also wrecked another teenager’s life and Derek’s 16-year-old attacker will now spend many years behind bars. It demonstrates the devastating consequences of carrying knives and the serious harm it has on our communities.”

The teenager is due to be sentenced this afternoon.