A man is undergoing surgery in Nelson after he was stabbed on a fishing boat.
The incident happened about 3.30am today on a fishing vessel berthed at the Nelson Wharf.
Police spokeswoman Barbara Dunn said the victim, who was a crew member on the boat, was taken to Nelson Hospital with serious injuries and was currently undergoing surgery.
A 30-year-old man who also worked on the vessel has been arrested in relation to the incident.
The charges faced by the man are yet to be confirmed, but he was expected to appear in the Nelson District Court this afternoon.
No one else was believed to be involved in the incident, Dunn said.