A man has been arrested in connection with a stabbing outside a Blenheim Road carwash in Riccarton.

Detective Sergeant James Haigh said police launched an investigation after the victim was brought to Christchurch Hospital in critical condition last night.

The incident occurred when two cars were stopped at a red light. A man exited one of the vehicles and attacked the victim, who was in the other car.

Through CCTV footage, public information, and strong investigative work, a 26-year-old man was identified and arrested. He is scheduled to appear in the Christchurch District Court tomorrow, charged with wounding with intent to cause grievous bodily harm.

Police thanked the public for their assistance with information and footage.