Detectives investigating the fatal stabbing of a 17-year-old boy on a north London street have arrested another teenager on suspicion of murder.

Nedim Bilgin died on Tuesday after being stabbed with a large knife on Caledonian Road, Islington, 300 metres from his home. A postmortem showed that a single stab wound killed him. It is understood he was stabbed at least twice.

The Metropolitan police said three people aged 16, 17 and 18 arrested on Tuesday on suspicion of murder had all been released on bail.

An 18-year-old arrested on Thursday on suspicion of murder remained in custody, police said. A 22-year-old man arrested on Thursday on suspicion of assisting an offender was released on bail.

Police have said Nedim’s mother was told at her home by local people that her son had been hurt and rushed to the scene. There she saw her son lying on the ground as paramedics fought to save his life. His injuries were too severe and he was pronounced dead about 30 minutes after the stabbing.

He was the second teenager to die after a knife attack this year in London, where there have been eight homicides so far this year. There were 135 homicides in London in 2018, an increase on 2017.

Police do not believe robbery was a motive for the attack on the teenager. A bicycle was found close to the scene and detectives are trying to establish to whom it belonged and whether Nedim had been riding one before the attack. Knives were recovered near the scene of the attack, police said.