Ben Kinsella's family have released a chilling essay which describes in grizzly detail what it would be like to be knifed as four teenagers are arrested over his death.

The four, all in their late teens, are being held at north and east London police stations after being arrested on Monday and early on Tuesday.

Two 16-year-olds were initially arrested but were released.

The family released the creative essay which in striking similarities to his own death, he described how he stared at his killer as the blood seeped from his body.

He wrote: "The pavement feels so very cold on my so very punctured back. Everything feels cold. Numbness persists."

Ben talks about not being scared and even forgives his killer, saying: "I had this burning desire to hate the animal who took me away from life yet, although I don't know why, I'd forgiven the murderer."

Meanwhile hundreds of teenagers have protested against escalating knife crime in Islington.

Many wore T-shirts with slogans such as "RIP Ben. "You're an Angel", "Stop Knife Violence" and "You're Always in Our Hearts".

Actress Linda Robson has called for an end to knife crime in the wake of the stabbing of the 16-year-old.

The Birds of a Feather star is a friend of the Kinsella family and her son Louis was with Ben when he died.

Robson spoke of her fears for her own children after revealing that Louis had tried to save Ben's life.

Louis and Ben - whose sister Brooke is also an actress - were among a group of friends that went out to Shillibeers club in Islington on Saturday night.

Police said several youths were ejected and the trouble continued in the street, leading to Ben being fatally stabbed at the junction of North Road and York Way.

Robson said: "Just as my husband was arriving to pick my son up, Louis rang - he was in a terrible state - to say that Ben had been stabbed.

"Louis thought he'd just been stabbed in the side and he put his cardie into the gaping wound and tried to keep Ben going and was talking to him and then later we found out that Ben had actually been stabbed six or seven times."

She added: "Every time our kids walk out of the door I can't breathe, I've got butterflies, I picture all this happening.

"That's what every parent feels. When our kids leave the house now we're petrified - are they going to come back?"

Ben was the 17th teenager to be killed in London so far this year, and the 12th to be stabbed to death.

His sister, Brooke, said: "Now truly is the time to stand up and put an end to this.

"Please, please let us learn from Ben and every other child that has been stolen from us.

"We always knew Ben would make a special mark in this world and although this is in the worst possible circumstances, hopefully he will be the one that finally puts an end to this."

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