The police are trying to piece together the events leading up to a stabbing just after midnight in Nelson.
They say a pair of men and a group of two men and two women got into a verbal and physical row at the corner of St Vincent and Natalie streets.
A 36-year-old man was stabbed in the stomach with a knife and was taken to Nelson Hospital, where he had surgery and is now recovering.
The police say two 18-year-old local men were arrested but they cannot lay charges until they work out what happened.
