Police were called multiple times to a group of men fighting on Park Road near Regent’s Park at around 3.45pm on September 27.
A video shows the men attacking each other in the middle of the road in front of halted traffic before a car drives straight into them.
Officers arrived and one man was treated for stab wounds that are not life-changing.
They arrested a 30-year-old man on suspicion of affray. He remains in custody while enquiries are ongoing.
Police continue to appeal to the public for information on the incident.
A Met Police spokesperson said: “Met Police received multiple reports of a large disturbance on Park Road, NW8 at around 15:48hrs on Saturday, 27 September.
“A group of men were witnessed fighting in the road before being involved in a collision with a single vehicl