Northern Territory Police are calling for witnesses in relation to a serious harm incident which occurred in Darwin city.

Two males, aged 27 and 32, got into a verbal altercation with a 20-year-old male at Uncle Sam's around 4:00am on Wednesday, 18 December.

The pair began walking down Smith Street when the 20-year-old male allegedly struck the 32-year-old male to the back of the head with a blunt weapon, causing minor swelling. A physical altercation took place between the 32-year-old and offender which culminated in the offender striking the 27-year-old male with his vehicle and driving away. Both victims were conveyed to Royal Darwin Hospital.

Serious Crime Squad detectives arrested the 20-year-old male this morning. He remains in custody and is expected to be charged with unlawfully cause serious harm and going armed in public.

Anyone who witnessed the incident is urged to contact police on 131444 or Crime Stoppers on 1800 333 000. Please quote reference number 9163095.