Elianne Andam begged her killer to stop as he stabbed her in the neck, jurors have heard.

Hassan Sentamu, then 17, lashed out at the 15-year-old with a kitchen knife outside a shopping centre in Croydon, south London, after refusing to hand back items belonging to Elianne’s friend, with whom he had split up 10 days before.

When Elianne grabbed a bag of his clothes in solidarity with her friend, Mr Sentamu chased after her, produced a knife and repeatedly stabbed her, the Old Bailey has heard.

Mr Sentamu admits the manslaughter of Elianne but denies murder on the basis his responsibility was diminished due to his autism.

When Elianne collapsed outside the Whitgift Centre, Mr Sentamu fled and dumped the knife nearby, jurors were told.

He was arrested within 90 minutes after a police officer stopped a bus near his home in New Addington.

Mr Sentamu’s ex-girlfriend described the events leading up to the attack on her friend, before school on the morning of 27 September 2023.

In a video interview played in court, she told police she realised something was wrong when Mr Sentamu, now 18, turned up for a planned exchange of their belongings wearing gloves and a mask, which she said was “out of character”.

She knew he had an “anger issue” – and likened his demeanour that morning to a character from the London-based crime drama Top Boy.

She said: “I thought he was gonna hit me. I thought that he had something on him because… watching shows and stuff like, for example Top Boy, whenever someone’s about to get killed they always have on specifically black gloves.

“I’ve never seen him wear black gloves; it’s not cold outside.”

Having given him his bag of possessions, she said she then asked for him to return her belongings.

“He looked at me… and rolled his eyes a bit.. and said, ‘I don’t want to hurt you’… not like in an emotional way… like he’s warning me.”

She went on: “I was saying ‘Where’s my teddy [bear]? Where’s my teddy? Where’s my teddy?”

The girl, who cannot be identified for legal reasons, said she was annoyed and wanted to get to school, at which point Elianne grabbed Mr Sentamu’s belongings.

She said: “Elianne ran behind him, grabbed the bag and started running and laughing as a joke. It was the type of thing that Elianne would have done.

“At first I was laughing a bit ‘cos it was a joke and then I got scared ‘cos then Hassan got mad.”

She told police: “He then lifted up his hoodie quick, pulled out something and I saw a big knife.

“I turned around for one second then I saw her on the floor like trying to say ‘stop’, basically with her hand out. He was there like over her, bending.

“I just saw Elianne on the floor, like backing up on the floor with her hand out like this, basically saying ‘stop, stop, stop’ and I’m pretty sure I saw him bend and like try and do something else, like stab her again.”

Before arranging the meeting, the girl said Mr Sentamu had got angry and sworn at her during an argument over the phone.

She said: “I just told him never ever speak to me like that ever again, ‘cos I said I’ve never been spoken to like that in my life.

“I said no man should speak to a girl like that and he said, ‘oh well, there’s a first time for everything’.”

Earlier, PC Peter Nolan gave evidence about the arrest of Mr Sentamu.

Prosecutor Alex Chalk KC asked the officer what he noticed about the teenager he had detained.

PC Nolan replied: “I believed what I saw was a smear of blood on his thumb.”

Mr Sentamu, who was studying sports science at Croydon College, denies both murder and a charge of illegal possession of a knife, claiming he had a “lawful reason” to be carrying it.

The trial continues.

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