A 14-year-old boy was stabbed in the stomach with a 10-inch kitchen knife on a busy north London street as onlookers pleaded with the attacker not to do it, a witness said.

Two men and what appeared to be two young teenagers were involved in a fight for a few minutes before a third teenager ran towards them carrying the “gleaming” weapon, a local resident said.

The victim is in a serious but stable condition after being airlifted to hospital, the Metropolitan Police said, after the incident on Fairbridge Road near Archway shortly before 7pm on Sunday.

Fairbridge Road
A 14-year-old boy was stabbed in front of horrified onlookers (John Stilwell/PA)

An 11-year-old boy who was arrested on suspicion of attempted murder is no longer a suspect, the force added.

In a statement they said: “Following initial enquiries the boy was de-arrested and released from custody.”

Mayor of London Sadiq Khan said: “Incidents like this have a devastating impact on families and our communities and we need to send the message that they will not be tolerated.

“Politicians, the police and all Londoners must unite in saying it is never acceptable to carry a knife – and it does not make you safer.”

Local resident Amina Taylor, who said all those involved were white, said she saw the victim stabbed in the stomach with a large knife.

Fairbridge Road
Officers have appealed for witnesses (John Stilwell/PA)

The 40-year-old journalist told how she heard shouting outside her flat overlooking Fairbridge Road and went to her balcony from where she saw a fight involving two men and two young teenagers.

Within a few minutes another young boy ran down the road towards the group carrying what looked like a kitchen knife as onlookers shouted for the fight to stop, she said.

“We could all see the knife in his hand. It was that big,” she said.

“You could hear the screams of ‘No, stop it, don’t do anything, don’t be stupid’ and he went for (one of the adults) first but then he was kind of swinging wildly and then he just thrust the knife into the stomach of the teenager.”

She said she was shocked to see “somebody who is clearly barely taller than my nine-year-old son coming down with a weapon in his hand”.

She described seeing the “big” and “cumbersome” weapon gleaming as she watched from her second floor flat.

In a statement, the Met said: “At this early stage officers retain an open mind as to motive.”

Police have appealed for anyone who saw the stabbing to contact them.

Police tape, guarded by uniformed officers, marked off a cordon at the end of Fairbridge Road next to a neighbourhood cafe.

A bag of what looked like clothes lay outside.

Shopkeer Abdullah Ozcelik, who works nearby, said he was not surprised the violence involved youngsters or that it happened locally.

He said: “These people are just little children. It should be unbelievable. It should not happen to anyone.

“Obviously it is a horrible thing to happen because people are scared. It is a bad thing for the area and a bad thing for business.

“It is more than one life that is probably ruined by this – it is the boy who was stabbed and whoever stabbed him.”

He said a crowd gathered when ambulances, a helicopter and police rushed to the scene and this was when he knew something “horrible” had happened.