Multiple police vehicles and armed police are swarming a Christchurch street - where four people were injured in a late night altercation

Emergency services have been at Northcote's Hoani Street, near Greers Road, since 9.30 last night.

Police say four are injured - one critically, and another seriously.

They believe the parties involved were known to each other, and there's minimal risk to the public.

Herald reporter Jazlyn Whales has been speaking with a neighbour who says he didn't hear the initial incident, but when he woke in the night, there were so many emergency vehicles it looked like daylight.