The GCSE student and brother of former EastEnders actress Brooke Kinsella was knifed to death when he was caught up in a fight that spilled out of a north London bar early on Sunday.

A Metropolitan Police spokesman said: "Four people have been arrested in connection with the death of Ben Kinsella. They are currently in custody in London police stations."

Two 16-year-old boys arrested earlier in connection with the investigation have been bailed to return to a north London police station on a date in late August.

Meanwhile, Birds Of A Feather star Linda Robson has made an emotional appeal for tougher penalties for carrying knives as she spoke of the desolation of the family of murdered teenager Ben Kinsella.

The TV actress said the grief of the family of the 16-year-old, who was stabbed to death in the early hours of Sunday morning after visiting Shillibeers club in Islington, was unimaginable.

Her teenage son, Louis, who was close friends with Ben, cradled the stabbed schoolboy as he lay dying, she revealed, but was unaware at the time of his multiple injuries.

Robson called on parents to take responsibility for their children and know about their whereabouts.

Ben, who was due to receive his GCSE results this summer and was a popular pupil at Holloway School in Islington, north London, was knifed to death when he became caught up in a fight which spilled out of a north London bar early on Sunday.

His sister, Brooke Kinsella, 24, best known for playing Kelly Taylor in EastEnders, paid tribute to a "true angel" as she spoke of her family's loss on Monday. Pleading for young people to put away their knives, she told a police press conference that her family was determined to fight in Ben's memory to make the streets safer.