Police have made further arrests in connection with the fatal stabbing of Ben Kinsella in London at the weekend, Scotland Yard said today.

It is believed that four teenagers are in custody. Two 16-year-olds who were arrested at the weekend were released on bail.

The bright, popular, 16-year-old schoolboy was stabbed six or seven times at 2am on Sunday when he became caught up in a violent row outside a club in Islington, North London.

His family — parents Deborah and George, and his three sisters, Brooke, a former EastEnders actress, Jade and Georgia — spoke yesterday of their grief and loss, and made an emotional plea for young people to put down their knives.

After Ben died, the family discovered a GCSE coursework essay that he had written in which he described being stabbed to death and meeting lost relatives in heaven, it emerged today. The teenager included vivid details that bore striking similarities to his own fate, according to reports.

In one section Ben wrote about staring up at his killer and wondering whether he deserved to die. "I knew I was gone and couldn’t come back. I just wished I had the strength to say goodbye. I was dead now," he wrote.

Linda Robson, the Birds of a Feather actress whose teenage son, Louis, was close friends with Ben and tried to comfort him as he lay bleeding in the street, confirmed that she had seen the essay on the table at the family home on Sunday.

"That poor, poor family. You just can’t believe what they are going through, you really can’t," Ms Robson told GMTV this morning.

"Debbie was making tea and trying to keep calm, I think for the girls, and George was just sort of wandering around and the girls were wailing and wearing Ben’s clothes and finding all this GCSE coursework . . ."

Hundreds of teenagers gathered today in North London to protest at escalating knife crime, after Ben's murder.

Wearing white T-shirts, they stood at the steps of Islington Town Hall in North London to voice their concerns at the recent spate of killings. Many wore T-shirts with slogans such as “RIP Ben. ”You’re an Angel“, ”Stop Knife Violence“ and ”You’re Always in Our Hearts“.

Louis and Ben were among a group of friends who went out to Shillibeers club in Islington on Saturday night, she said. Robson said she phoned her son every half an hour and had been reassured that the teenagers were not drinking and "everything was fine".

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