Police were scrambled to Walthamstow after four men suffered knife wounds after a fight on Bonfire Night.
They were treated by paramedics at the scene before being taken to hospital.
Their injuries have been assessed as non-life threatening and all have been arrested on suspicion of affray.
The incident unfolded at just before 9.30pm on Sunday in Hoe Street.
A police statement said: "The three men were treated by paramedics at the scene before being taken to hospital. A fourth man was also found with stab injuries and he was taken to hospital.
"The conditions of the four men have been assessed as non life-threatening. All four have been arrested on suspicion of affray and they remain in police custody."
Anyone with information is asked to call police on 101 or to remain anonymous Crimestoppers on 0800 555 111.
