A commuter has described his horror at seeing a boy attacked on a bus in Caledonian Road, in an incident believed to be linked to a stabbing on a nearby Overground platform.

The bus passenger told how a gang of boys on bikes chased their victim onto the top deck of the number 91 before beating him up and fleeing.

It happened yesterday at about 2.45pm while, yards away, Caledonian Road and Barnsbury station was being cleared by police following an attack on a 17-year-old boy.

He was stripped to his underwear and given breathing apparatus before being taken to hospital with serious injuries.

About 25 people were said to have descended on the station in the build-up to the attacks and witnesses saw another boy chased onto a 91 bus by a gang of boys on bikes minutes before police arrived.

A passenger on the bus today told the Gazette: “I was on the top deck and going by the station I saw a guy run for the bus. I just thought it was normal but he got on the bus and a group of kids on bikes tried to stop the bus.

“They pressed the emergency button to open the door. The driver opened the door at the bus stop and the kids ran onto the bus, which made it worse because they came up from both stairs.

“They attacked him on the top deck where I was, then got off. Some got on bikes and some ran towards the estate.”

Another witness, Colin Magan, also saw a lot of boys on bikes stop the bus and chase a boy onto it.

Mother-of-two Claire Gibbs, who lives nearby, said she was too scared to let her children out in the streets these days.

“It’s always going on round here,” she said. “Everyone knows everyone but people won’t open their mouths.”

A 15-year-old boy has been arrested on suspicion of causing GBH. British Transport Police officers are looking to trace a second man believed to be connected to the attack.

He is black and of medium build, and was wearing a black baseball cap, patterned blue jumper and dark jacket.

Investigating officer Det Sgt Av Dhaliwal said: “We are working to establish the exact circumstances of what happened at the station.

“If you have any information, I urge you to get in touch as soon as possible.

“Officers are patrolling the area and will be over the coming days so if you have any concerns at all, please don’t hesitate to talk to them.”

Anyone with information is asked to contact British Transport Police on 0800 40 50 40 or text 61016, quoting 329 of 25/08.