Police were called to a residential property in Harlech St just before 4am, where someone was found to have serious stab wound injuries, a police spokeswoman said.
The person was taken to Oamaru Hospital, and was in a stable condition. Another person received a minor injury.
A reporter at the scene said that shortly after 11.30am a 28-year-old man walked barefoot, with his hands in the air, towards police officers stationed outside the property.
He was spoken to by officers, before being put in a police car.
The spokeswoman confirmed the man was arrested and charged with attempted murder and wounding with intent to cause grievous bodily harm.
He is due to appear in the Oamaru District Court today.
Asked if the accused was known to the victims, or in the same lockdown bubble, the spokeswoman said as the matter was before the court, police had no further comment.
A police scene guard remained outside the property for most of yesterday.
