The boys all aged 16, and aged 17 and all were arrested on suspicion of murder after warrants were executed in north London this morning.

Stefan’s family have been informed of this development. They are being supported by specialist officers.

Police were called at approximately 1.05am on Friday, 28 July to reports of a man suffering a stab injury in Whitchurch Lane.

Officers attended along with the London Ambulance Service and London’s Air Ambulance.

Despite the efforts of the emergency services, Stefan died at the scene.

A post-mortem examination held on Saturday, 29 July gave the cause of death as a stab wound to the chest.

Detectives from the Met’s Specialist Crime Command are leading the investigation and enquiries are ongoing.

Detective Chief Inspector Neil John, who is leading the investigation, said: “My thoughts are with Stefan’s family as they come to terms with this awful news. We will do everything we can to support them and bring whoever is responsible to justice.

“These arrests mark significant progress in what is a fast-moving investigation. We believe there are outstanding suspects and our work to trace those people continues.

“Our work is far from finished and we need the public’s help. I remain keen to hear from anyone who has information, no matter how small or insignificant it might seem.

I would also like to hear from any drivers who were passing through the area and have dash cam footage to come forward.

Information can be provided to the incident room by calling 020 8358 0100. Alternatively, call 101 quoting CAD 334/28Jul.

You can also provide information anonymously to the independent charity Crimestoppers on 0800 555 111