Three men and one woman have been arrested on suspicion of attempted murder after the incident in Old Street at 2.20am this morning (March 15).
Police had initially received reports of an assault in the street.
A man aged in his 20s was rushed from the scene by London Ambulance Service (LAS) to a major trauma centre.
He had been stabbed in the groin, and remains in hospital in a critical condition.
The four people arrested were stopped close to Shoreditch Park just after 3am, and remain in custody at this time.
A LAS spokesperson said that an ambulance crew, an advanced paramedic, a paramedic in a fast response car and an incident response officer were all sent to the scene.
A trauma team in a car from London’s Air Ambulance also responded to the incident. Paramedics arrived less than four minutes after the first callout.
Old Street was shut to traffic by a large police cordon which stretched from the junctions with Charlotte Road and Curtain Road until around 5pm this afternoon.
Charlotte Road was also shut by police. The cordon had forced the diversion of bus routes 55 and 243.
