Three men have been arrested on suspicion of murdering a schoolboy who was stabbed to death while riding his bike with friends.

Alan Cartwright, 15, died from a single stab wound to the chest after he was attacked as he rode along Caledonian Road in Islington on Friday evening.

Detectives were this morning questioning a 21 year-old man, an 18-year-old man and a 17-year-old boy on suspicion of his murder, a spokesman for Scotland Yard said.

The 18-year-old was held after he attended a north London police station, while the 21-year-old and 17-year-old were arrested at separate addresses in Camden, he added.

All three were being held in custody at police stations in north and central London.

Yesterday Alan's family made an emotional appeal for witnesses to come forward after the Holloway High School pupil was killed in what was described as a "senseless" attack.

His mother Michelle Watson, 39, said: "I would say to witnesses, if you've got any sort of conscience come forward because a brother and son is dead.

"I feel angry, I want somebody found for this. I just feel numb."